In one of my WinForms applications, I have a window with a ComboBox for the user to select a customer from.
The customers in this list box are in this format : "CustomerID - CustomerN开发者_Python百科ame", for example "004540 - NorthWind Traders"
The native WinForms combobox has an autocomplete feature built-in and it works well: the problem is that it only works by matching from the beginning of the string of each item of the combobox's list and not from anywhere (substring).
What I would like my users to be able to do is to either type of the CustomerID or CustomerName, as senior users are familiar with most CustomerIDs while new recruits would benefit from being able to type the CustomerName in and get the AutoComplete anyway. That means that I actually want to look for the best match from the list where the inputted text is a substring of the ComboBox item.
A solution often suggested for this kind of scenario is to create a hidden list box that only shows up when the user types, but I'm not happy with that as it feels like a quick hack and is not easily reusable, and may look and behave inconsistently compared to the standard ComboBox control.
I've tried to implement this myself using the DroppedDown property to make the list appear and use SelectedIndex to set the item but the content of the combobox's textbox is reset when I do that, while I only would like the "best matching item" to be highlighted from the ComboBox lists (I need "Suggest" and not "Append", Append-mode can not be really be used with substring-matching anyway).
I think that there must be a better way? If anyone knows of a custom / 3rd Party control doing this, I'm not against buying one either.
Thanks.
PS: I am programming in C# for WinForms, with .Net Framework 3.5.
Here is the C# version. It has a lot of options to it.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
this.Load += new EventHandler(this.Form1_Load);
InitializeComponent();
}
private clsCustomAutoCompleteTextbox ClsCustomAutoCompleteTextbox1 = null;
private List<string> MasterList = new List<string> ();
public void Form1_Load(object sender, System.EventArgs e) {
this.ClsCustomAutoCompleteTextbox1 = new clsCustomAutoCompleteTextbox();
this.ClsCustomAutoCompleteTextbox1.AutoCompleteFormBorder = System.Windows.Forms.FormBorderStyle.None;
this.ClsCustomAutoCompleteTextbox1.AutoCompleteList = null;
this.ClsCustomAutoCompleteTextbox1.Location = new System.Drawing.Point(27, 57);
this.ClsCustomAutoCompleteTextbox1.Name = "clsCustomAutoCompleteTextbox1";
this.ClsCustomAutoCompleteTextbox1.OnEnterSelect = true;
this.ClsCustomAutoCompleteTextbox1.SelectionMethods = clsCustomAutoCompleteTextbox.SelectOptions.OnEnterSingleClick;
this.ClsCustomAutoCompleteTextbox1.SelectTextAfterItemSelect = true;
this.ClsCustomAutoCompleteTextbox1.ShowAutoCompleteOnFocus = false;
this.ClsCustomAutoCompleteTextbox1.Size = new System.Drawing.Size(232, 20);
this.ClsCustomAutoCompleteTextbox1.TabIndex = 0;
this.Controls.Add(this.ClsCustomAutoCompleteTextbox1);
this.ClsCustomAutoCompleteTextbox1.BeforeDisplayingAutoComplete +=
new EventHandler<clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs>(BeforeDisplayingAutoComplete);
List<string> L;
L = new List<string>();
L.Add("123123 - Bob");
L.Add("534543 - Sally");
L.Add("123123 - George");
L.Add("34213 - Happy");
MasterList = L;
this.ClsCustomAutoCompleteTextbox1.AutoCompleteList = L;
}
private void BeforeDisplayingAutoComplete(object sender, clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs e) {
string Name = this.ClsCustomAutoCompleteTextbox1.Text.ToLower();
List<string> Display = new List<string> ();
foreach (string Str in MasterList) {
if ((Str.ToLower().IndexOf(Name) > -1)) {
Display.Add(Str);
}
}
e.AutoCompleteList = Display;
e.SelectedIndex = 0;
}
}
public class clsCustomAutoCompleteTextbox : TextBox
{
private bool First = true;
private object sender;
private clsAutoCompleteEventArgs e;
public List<string> test = new List<string> ();
public int Tabs = 0;
private int mSelStart;
private int mSelLength;
private List<string> myAutoCompleteList = new List<string> ();
private ListBox myLbox = new ListBox();
private Form myForm = new Form();
private Form myParentForm;
private bool DontHide = false;
private bool SuspendFocus = false;
private clsAutoCompleteEventArgs Args;
private Timer HideTimer = new Timer();
private Timer FocusTimer = new Timer();
private bool myShowAutoCompleteOnFocus;
private System.Windows.Forms.FormBorderStyle myAutoCompleteFormBorder = FormBorderStyle.None;
private bool myOnEnterSelect;
private int LastItem;
private SelectOptions mySelectionMethods = (SelectOptions.OnDoubleClick | SelectOptions.OnEnterPress);
private bool mySelectTextAfterItemSelect = true;
private List<string> value;
private int Cnt = 0;
public bool SelectTextAfterItemSelect
{
get
{
return mySelectTextAfterItemSelect;
}
set
{
mySelectTextAfterItemSelect = value;
}
}
[System.ComponentModel.Browsable(false)]
public SelectOptions SelectionMethods
{
get
{
return mySelectionMethods;
}
set
{
mySelectionMethods = value;
}
}
public bool OnEnterSelect
{
get
{
return myOnEnterSelect;
}
set
{
myOnEnterSelect = value;
}
}
public System.Windows.Forms.FormBorderStyle AutoCompleteFormBorder
{
get
{
return myAutoCompleteFormBorder;
}
set
{
myAutoCompleteFormBorder = value;
}
}
public bool ShowAutoCompleteOnFocus
{
get
{
return myShowAutoCompleteOnFocus;
}
set
{
myShowAutoCompleteOnFocus = value;
}
}
public ListBox Lbox
{
get
{
return myLbox;
}
}
public List<string> AutoCompleteList { get; set; }
public event EventHandler<clsAutoCompleteEventArgs> BeforeDisplayingAutoComplete;
public event EventHandler<clsItemSelectedEventArgs> ItemSelected;
public enum SelectOptions
{
None = 0,
OnEnterPress = 1,
OnSingleClick = 2,
OnDoubleClick = 4,
OnTabPress = 8,
OnRightArrow = 16,
OnEnterSingleClick = 3,
OnEnterSingleDoubleClicks = 7,
OnEnterDoubleClick = 5,
OnEnterTab = 9,
}
public class clsAutoCompleteEventArgs : EventArgs
{
private List<string> myAutoCompleteList;
private bool myCancel;
private int mySelectedIndex;
private List<string> value;
public int SelectedIndex
{
get
{
return mySelectedIndex;
}
set
{
mySelectedIndex = value;
}
}
public bool Cancel
{
get
{
return myCancel;
}
set
{
myCancel = value;
}
}
public List<string> AutoCompleteList { get; set; }
}
public override string SelectedText
{
get
{
return base.SelectedText;
}
set
{
base.SelectedText = value;
}
}
public override int SelectionLength
{
get
{
return base.SelectionLength;
}
set
{
base.SelectionLength = value;
}
}
public clsCustomAutoCompleteTextbox()
{
HideTimer.Tick += new EventHandler(HideTimer_Tick);
FocusTimer.Tick += new EventHandler(FocusTimer_Tick);
myLbox.Click += new EventHandler(myLbox_Click);
myLbox.DoubleClick += new EventHandler(myLbox_DoubleClick);
myLbox.GotFocus += new EventHandler(myLbox_GotFocus);
myLbox.KeyDown += new KeyEventHandler(myLbox_KeyDown);
myLbox.KeyUp += new KeyEventHandler(myLbox_KeyUp);
myLbox.LostFocus += new EventHandler(myLbox_LostFocus);
myLbox.MouseClick += new MouseEventHandler(myLbox_MouseClick);
myLbox.MouseDoubleClick += new MouseEventHandler(myLbox_MouseDoubleClick);
myLbox.MouseDown += new MouseEventHandler(myLbox_MouseDown);
this.GotFocus += new EventHandler(clsCustomAutoCompleteTextbox_GotFocus);
this.KeyDown += new KeyEventHandler(clsCustomAutoCompleteTextbox_KeyDown);
this.Leave += new EventHandler(clsCustomAutoCompleteTextbox_Leave);
this.LostFocus += new EventHandler(clsCustomAutoCompleteTextbox_LostFocus);
this.Move += new EventHandler(clsCustomAutoCompleteTextbox_Move);
this.ParentChanged += new EventHandler(clsCustomAutoCompleteTextbox_ParentChanged);
}
override protected void OnKeyUp(System.Windows.Forms.KeyEventArgs e)
{
base.OnKeyUp(e);
ShowOnChar(new string(((char)(e.KeyValue)),1));
}
private void ShowOnChar(string C)
{
if (IsPrintChar(C))
{
this.ShowAutoComplete();
}
}
private bool IsPrintChar(int C)
{
return IsPrintChar(((char)(C)));
}
private bool IsPrintChar(byte C)
{
return IsPrintChar(((char)(C)));
}
private bool IsPrintChar(char C)
{
return IsPrintChar(C.ToString());
}
private bool IsPrintChar(string C)
{
if (System.Text.RegularExpressions.Regex.IsMatch(C, "[^\\t\\n\\r\\f\\v]"))
{
return true;
}
else
{
return false;
}
}
private void clsCustomAutoCompleteTextbox_GotFocus(object sender, System.EventArgs e)
{
if ((!this.SuspendFocus
&& (this.myShowAutoCompleteOnFocus
&& (this.myForm.Visible == false))))
{
this.ShowAutoComplete();
}
}
private void clsCustomAutoCompleteTextbox_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
if (!SelectItem(e.KeyCode, false, false))
{
if ((e.KeyCode == Keys.Up))
{
if ((myLbox.SelectedIndex > 0))
{
MoveLBox((myLbox.SelectedIndex - 1));
}
}
else if ((e.KeyCode == Keys.Down))
{
MoveLBox((myLbox.SelectedIndex + 1));
}
}
}
new void SelectAll()
{
}
private void MoveLBox(int Index)
{
try
{
if ((Index
> (myLbox.Items.Count - 1)))
{
Index = (myLbox.Items.Count - 1);
}
myLbox.SelectedIndex = Index;
}
catch
{
}
}
private void clsCustomAutoCompleteTextbox_Leave(object sender, System.EventArgs e)
{
DoHide(sender, e);
}
private void clsCustomAutoCompleteTextbox_LostFocus(object sender, System.EventArgs e)
{
DoHide(sender, e);
}
private void clsCustomAutoCompleteTextbox_Move(object sender, System.EventArgs e)
{
MoveDrop();
}
private void clsCustomAutoCompleteTextbox_ParentChanged(object sender, System.EventArgs e)
{
if (myParentForm != null) myParentForm.Deactivate -= new EventHandler(myParentForm_Deactivate);
myParentForm = GetParentForm(this);
if (myParentForm != null) myParentForm.Deactivate += new EventHandler(myParentForm_Deactivate);
}
private void HideTimer_Tick(object sender, System.EventArgs e)
{
MoveDrop();
DoHide(sender, e);
Cnt++;
if ((Cnt > 300))
{
if (!AppHasFocus(""))
{
DoHideAuto();
}
Cnt = 0;
}
}
private void myLbox_Click(object sender, System.EventArgs e)
{
}
private void myLbox_DoubleClick(object sender, System.EventArgs e)
{
}
private bool SelectItem(Keys Key, bool SingleClick)
{
return SelectItem(Key, SingleClick, false);
}
private bool SelectItem(Keys Key)
{
return SelectItem(Key, false, false);
}
private bool SelectItem(Keys Key, bool SingleClick, bool DoubleClick)
{
// Warning!!! Optional parameters not supported
// Warning!!! Optional parameters not supported
// Warning!!! Optional parameters not supported
bool DoSelect = true;
SelectOptions Meth = SelectOptions.None;
LastItem = -1;
if (((this.mySelectionMethods & SelectOptions.OnEnterPress) > 0) && (Key == Keys.Enter))
{
Meth = SelectOptions.OnEnterPress;
}
else if (((this.mySelectionMethods & SelectOptions.OnRightArrow) > 0) && Key == Keys.Right)
{
Meth = SelectOptions.OnRightArrow;
}
else if (((this.mySelectionMethods & SelectOptions.OnTabPress) > 0) && Key == Keys.Tab)
{
Meth = SelectOptions.OnTabPress;
}
else if (((this.mySelectionMethods & SelectOptions.OnSingleClick) > 0) && SingleClick)
{
Meth = SelectOptions.OnEnterPress;
}
else if (((this.mySelectionMethods & SelectOptions.OnDoubleClick) > 0) && DoubleClick)
{
Meth = SelectOptions.OnEnterPress;
}
else
{
DoSelect = false;
}
LastItem = myLbox.SelectedIndex;
if (DoSelect)
{
DoSelectItem(Meth);
}
return DoSelect;
}
public class clsItemSelectedEventArgs : EventArgs
{
private int myIndex;
private SelectOptions myMethod;
private string myItemText;
public clsItemSelectedEventArgs()
{
}
public clsItemSelectedEventArgs(int Index, SelectOptions Method, string ItemText)
{
myIndex = Index;
myMethod = Method;
myItemText = ItemText;
}
public string ItemText
{
get
{
return myItemText;
}
set
{
myItemText = value;
}
}
public SelectOptions Method
{
get
{
return myMethod;
}
set
{
myMethod = value;
}
}
public int Index
{
get
{
return myIndex;
}
set
{
myIndex = value;
}
}
}
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();
[System.Runtime.InteropServices.DllImport("user32.dll")]
static extern int GetWindowThreadProcessId(IntPtr hWnd, ref int ProcessID);
private bool AppHasFocus(string ExeNameWithoutExtension)
{
bool Out = false;
// Warning!!! Optional parameters not supported
int PID = 0;
if ((ExeNameWithoutExtension == ""))
{
ExeNameWithoutExtension = System.Diagnostics.Process.GetCurrentProcess().ProcessName;
}
IntPtr activeHandle = GetForegroundWindow();
GetWindowThreadProcessId(activeHandle, ref PID);
if ((PID > 0))
{
// For Each p As Process In Process.GetProcessesByName(ExeNameWithoutExtension)
if ((PID == System.Diagnostics.Process.GetCurrentProcess().Id))
{
Out = true;
}
// Next
}
return Out;
}
private void SaveSelects()
{
this.mSelStart = this.SelectionStart;
this.mSelLength = this.SelectionLength;
}
private void LoadSelects()
{
this.SelectionStart = this.mSelStart;
this.SelectionLength = this.mSelLength;
}
private void ShowAutoComplete()
{
Args = new clsAutoCompleteEventArgs();
// With...
Args.Cancel = false;
Args.AutoCompleteList = this.myAutoCompleteList;
if ((myLbox.SelectedIndex == -1))
{
Args.SelectedIndex = 0;
}
else
{
Args.SelectedIndex = myLbox.SelectedIndex;
}
if (BeforeDisplayingAutoComplete != null) BeforeDisplayingAutoComplete(this, Args);
this.myAutoCompleteList = Args.AutoCompleteList;
// If Me.myAutoCompleteList IsNot Nothing AndAlso Me.myAutoCompleteList.Count - 1 < Args.SelectedIndex Then
// Args.SelectedIndex = Me.myAutoCompleteList.Count - 1
// End If
if ((!Args.Cancel && (Args.AutoCompleteList != null) && Args.AutoCompleteList.Count > 0))
{
DoShowAuto();
}
else
{
DoHideAuto();
}
}
private void DoShowAuto()
{
SaveSelects();
myLbox.BeginUpdate();
try
{
myLbox.Items.Clear();
myLbox.Items.AddRange(this.myAutoCompleteList.ToArray());
this.MoveLBox(Args.SelectedIndex);
}
catch (Exception ex)
{
}
myLbox.EndUpdate();
myParentForm = GetParentForm(this);
if (myParentForm != null)
{
myLbox.Name = ("mmmlbox" + DateTime.Now.Millisecond);
if ((myForm.Visible == false))
{
myForm.Font = this.Font;
myLbox.Font = this.Font;
myLbox.Visible = true;
myForm.Visible = false;
myForm.ControlBox = false;
myForm.Text = "";
if (First)
{
myForm.Width = this.Width;
myForm.Height = 200;
}
First = false;
if (!myForm.Controls.Contains(myLbox))
{
myForm.Controls.Add(myLbox);
}
myForm.FormBorderStyle = FormBorderStyle.None;
myForm.ShowInTaskbar = false;
// With...
myLbox.Dock = DockStyle.Fill;
myLbox.SelectionMode = SelectionMode.One;
// Frm.Controls.Add(myLbox)
DontHide = true;
SuspendFocus = true;
myForm.TopMost = true;
myForm.FormBorderStyle = this.myAutoCompleteFormBorder;
myForm.BringToFront();
MoveDrop();
myForm.Visible = true;
myForm.Show();
MoveDrop();
HideTimer.Interval = 10;
this.Focus();
SuspendFocus = false;
HideTimer.Enabled = true;
DontHide = false;
LoadSelects();
}
}
}
void MoveDrop()
{
Point Pnt = new Point(this.Left, (this.Top
+ (this.Height + 2)));
Point ScreenPnt = this.PointToScreen(new Point(-2, this.Height));
// Dim FrmPnt As Point = Frm.PointToClient(ScreenPnt)
if (myForm != null)
{
myForm.Location = ScreenPnt;
// myForm.BringToFront()
// myForm.Focus()
// myLbox.Focus()
// Me.Focus()
}
}
void DoHide(object sender, EventArgs e)
{
HideAuto();
}
private void DFocus(int Delay)
{
// Warning!!! Optional parameters not supported
FocusTimer.Interval = Delay;
FocusTimer.Start();
}
private void DFocus()
{
DFocus(10);
}
private void DoHideAuto()
{
myForm.Hide();
HideTimer.Enabled = false;
FocusTimer.Enabled = false;
}
private void HideAuto()
{
if ((myForm.Visible && HasLostFocus()))
{
DoHideAuto();
}
}
private bool HasLostFocus()
{
bool Out = false;
if (this.myForm == null || myForm.ActiveControl != this.myLbox)
{
Out = true;
}
if (this.myParentForm == null || this.myParentForm.ActiveControl != this)
{
Out = true;
}
return Out;
}
private Form GetParentForm(Control InCon)
{
Control TopCon = FindTopParent(InCon);
Form Out = null;
if ((TopCon is Form))
{
Out = ((Form)(TopCon));
}
return Out;
}
private Control FindTopParent(Control InCon)
{
Control Out;
if ((InCon.Parent == null))
{
Out = InCon;
}
else
{
Out = FindTopParent(InCon.Parent);
}
return Out;
}
private void DoSelectItem(SelectOptions Method)
{
if (((this.myLbox.Items.Count > 0)
&& (this.myLbox.SelectedIndex > -1)))
{
string Value = this.myLbox.SelectedItem.ToString();
string Orig = this.Text;
this.Text = Value;
if (mySelectTextAfterItemSelect)
{
try
{
this.SelectionStart = Orig.Length;
this.SelectionLength = (Value.Length - Orig.Length);
}
catch (Exception ex)
{
}
}
else
{
// Me.SelectionStart = Me.Text.Length
// Me.SelectionLength = 0
}
clsItemSelectedEventArgs a;
a = new clsItemSelectedEventArgs();
a.Index = this.myLbox.SelectedIndex;
a.Method = Method;
a.ItemText = Value;
if (ItemSelected != null) ItemSelected(this, a);
//ItemSelected(this, new clsItemSelectedEventArgs(this.myLbox.SelectedIndex, Method, Value));
this.DoHideAuto();
}
}
private void myLbox_GotFocus(object sender, System.EventArgs e)
{
DFocus();
}
private void myLbox_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
SelectItem(e.KeyCode);
}
private void ProcessKeyEvents(KeyEventArgs e)
{
if ((e.KeyCode >= Keys.A) && (e.KeyCode <= Keys.Z))
base.OnKeyUp(e);
//Keys.Back;
//Keys.Enter;
//Keys.Left;
//Keys.Right;
//Keys.Up;
//Keys.Down;
//(Keys.NumPad0 & (e.KeyCode <= Keys.NumPad9));
//(Keys.D0 & (e.KeyCode <= Keys.D9));
}
private void myLbox_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
{
if (IsPrintChar(e.KeyChar))
{
// Me.OnKeyPress(e)
// Call MoveDrop()
}
}
private void myLbox_KeyUp(object sender, System.Windows.Forms.KeyEventArgs e)
{
if (IsPrintChar(e.KeyValue))
{
// Me.OnKeyUp(e)
// Call MoveDrop()
}
}
private void myLbox_LostFocus(object sender, System.EventArgs e)
{
DoHide(sender, e);
}
private void myLbox_MouseClick(object sender, System.Windows.Forms.MouseEventArgs e)
{
// If e.Button <> Windows.Forms.MouseButtons.None Then
SelectItem(Keys.None,true);
// End If
}
private void myLbox_MouseDoubleClick(object sender, System.Windows.Forms.MouseEventArgs e)
{
// If e.Button <> Windows.Forms.MouseButtons.None Then
SelectItem(Keys.None, false, true);
// End If
}
private void myForm_Deactivate(object sender, System.EventArgs e)
{
}
private void myParentForm_Deactivate(object sender, System.EventArgs e)
{
}
private void FocusTimer_Tick(object sender, System.EventArgs e)
{
this.Focus();
}
private void myLbox_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
myLbox_MouseClick(sender, e);
}
}
}
Well, I have some code for you to try. Its not a combo box, but it is an autocomplete text box with modifications that perform as you are requesting.
Copy the code into a new form. Then before doing anything else, save and build. Then go to the form designer and drag a new ClsCustomAutoCompleteTextbox onto your form.
Then you should be able to run it. I do realize that you are wanting C# (At least now I realize that). Try this in VB and see if this is what you want, and I can convert it to C#.
Public Class Form1
Dim MasterList As New List(Of String)
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim L As New List(Of String)
L.Add("123123 - Bob")
L.Add("534543 - Sally")
L.Add("123123 - George")
L.Add("34213 - Happy")
MasterList = L
Me.ClsCustomAutoCompleteTextbox1.AutoCompleteList = L
End Sub
Private Sub ClsCustomAutoCompleteTextbox1_BeforeDisplayingAutoComplete(ByVal sender As Object, ByVal e As clsCustomAutoCompleteTextbox.clsAutoCompleteEventArgs) Handles ClsCustomAutoCompleteTextbox1.BeforeDisplayingAutoComplete
Dim Name As String = Me.ClsCustomAutoCompleteTextbox1.Text.ToLower
Dim Display As New List(Of String)
For Each Str As String In MasterList
If Str.ToLower.IndexOf(Name) > -1 Then
Display.Add(Str)
End If
Next
e.AutoCompleteList = Display
e.SelectedIndex = 0
End Sub
End Class
#Region "clsCustomAutoCompleteTextbox"
Public Class clsCustomAutoCompleteTextbox
Inherits TextBox
Event BeforeDisplayingAutoComplete(ByVal sender As Object, ByVal e As clsAutoCompleteEventArgs)
Event ItemSelected(ByVal sender As Object, ByVal e As clsItemSelectedEventArgs)
Public test As New List(Of String)
Public Tabs As Integer = 0
Private Function GetLastFunction(Optional ByVal Deep As Integer = 1) As System.Reflection.MethodInfo
Dim ST As New StackTrace
Dim Frame As StackFrame = ST.GetFrame(Deep)
Return Frame.GetMethod()
End Function
Private Sub TempLogStart()
'Dim Meth As System.Reflection.MethodInfo = GetLastFunction(3)
'test.Add(Now & " - " & New String(" ", Tabs * 2) & "Started " & Meth.Module.Name & "." & Meth.Name)
'Tabs += 1
End Sub
Private Sub TempLogStop()
' Dim Meth As System.Reflection.MethodInfo = GetLastFunction(3)
' Tabs -= 1
' test.Add(Now & " - " & New String(" ", Tabs * 2) & "Stopped " & Meth.Module.Name & "." & Meth.Name)
End Sub
Public Enum SelectOptions
OnEnterPress = 1
OnSingleClick = 2
OnDoubleClick = 4
OnTabPress = 8
OnRightArrow = 16
OnEnterSingleClick = 3
OnEnterSingleDoubleClicks = 7
OnEnterDoubleClick = 5
OnEnterTab = 9
'OnItemChange = 32
End Enum
Private mSelStart As Integer
Private mSelLength As Integer
Private myAutoCompleteList As New List(Of String)
Private WithEvents myLbox As New ListBox
Private WithEvents myForm As New Form
Private WithEvents myParentForm As Form
Private DontHide As Boolean = False
Private SuspendFocus As Boolean = False
Dim Args As clsAutoCompleteEventArgs
WithEvents HideTimer As New Timer()
WithEvents FocusTimer As New Timer()
Private myShowAutoCompleteOnFocus As Boolean
Private myAutoCompleteFormBorder As System.Windows.Forms.FormBorderStyle = FormBorderStyle.None
Private myOnEnterSelect As Boolean
Private mySelectionMethods As SelectOptions = (SelectOptions.OnDoubleClick Or SelectOptions.OnEnterPress)
Private mySelectTextAfterItemSelect As Boolean = True
Public Property SelectTextAfterItemSelect() As Boolean
Get
Return mySelectTextAfterItemSelect
End Get
Set(ByVal value As Boolean)
mySelectTextAfterItemSelect = value
End Set
End Property
<System.ComponentModel.Browsable(False)> _
Public Property SelectionMethods() As SelectOptions
Get
Return mySelectionMethods
End Get
Set(ByVal value As SelectOptions)
mySelectionMethods = value
End Set
End Property
Public Property OnEnterSelect() As Boolean
Get
Return myOnEnterSelect
End Get
Set(ByVal value As Boolean)
myOnEnterSelect = value
End Set
End Property
Public Property AutoCompleteFormBorder() As System.Windows.Forms.FormBorderStyle
Get
Return myAutoCompleteFormBorder
End Get
Set(ByVal value As System.Windows.Forms.FormBorderStyle)
myAutoCompleteFormBorder = value
End Set
End Property
Public Property ShowAutoCompleteOnFocus() As Boolean
Get
Return myShowAutoCompleteOnFocus
End Get
Set(ByVal value As Boolean)
myShowAutoCompleteOnFocus = value
End Set
End Property
Public ReadOnly Property Lbox() As ListBox
Get
Return myLbox
End Get
End Property
Public Property AutoCompleteList() As List(Of String)
Get
Return myAutoCompleteList
End Get
Set(ByVal value As List(Of String))
myAutoCompleteList = value
End Set
End Property
Private Sub TryHideFormWindowsDeactivated()
End Sub
Private Declare Auto Function GetForegroundWindow Lib "user32.dll" () As IntPtr
Private Declare Auto Function GetWindowThreadProcessId Lib "user32.dll" (ByVal hWnd As IntPtr, ByRef ProcessID As Integer) As Integer
Private Function IsCurProcess(ByVal P As Process) As Boolean
Dim Ptr As IntPtr = P.MainWindowHandle
End Function
Private Function AppHasFocus(Optional ByVal ExeNameWithoutExtension As String = "") As Boolean
Dim Out As Boolean = False
Dim PID As Integer = 0
TempLogStart()
If ExeNameWithoutExtension = "" Then
ExeNameWithoutExtension = Process.GetCurrentProcess.ProcessName
End If
Dim activeHandle As IntPtr = GetForegroundWindow()
Call GetWindowThreadProcessId(activeHandle, PID)
If PID > 0 Then
'For Each p As Process In Process.GetProcessesByName(ExeNameWithoutExtension)
If PID = Process.GetCurrentProcess.Id Then
Out = True
'Exit For
End If
' Next
End If
TempLogStop()
Return Out
End Function
Private Sub SaveSelects()
Me.mSelStart = Me.SelectionStart
Me.mSelLength = Me.SelectionLength
End Sub
Private Sub LoadSelects()
Me.SelectionStart = Me.mSelStart
Me.SelectionLength = Me.mSelLength
End Sub
Private Sub ShowAutoComplete()
TempLogStart()
Args = New clsAutoCompleteEventArgs()
With Args
.Cancel = False
.AutoCompleteList = Me.myAutoCompleteList
If myLbox.SelectedIndex = -1 Then
.SelectedIndex = 0
Else
.SelectedIndex = myLbox.SelectedIndex
End If
End With
RaiseEvent BeforeDisplayingAutoComplete(Me, Args)
Me.myAutoCompleteList = Args.AutoCompleteList
'If Me.myAutoCompleteList IsNot Nothing AndAlso Me.myAutoCompleteList.Count - 1 < Args.SelectedIndex Then
' Args.SelectedIndex = Me.myAutoCompleteList.Count - 1
'End If
If Not Args.Cancel AndAlso Args.AutoCompleteList IsNot Nothing AndAlso Args.AutoCompleteList.Count > 0 Then
Call DoShowAuto()
Else
Call DoHideAuto()
End If
TempLogStop()
End Sub
Private Sub DoShowAuto()
Call SaveSelects()
TempLogStart()
Static First As Boolean = True
myLbox.BeginUpdate()
Try
myLbox.Items.Clear()
myLbox.Items.AddRange(Me.myAutoCompleteList.ToArray)
Call Me.MoveLBox(Args.SelectedIndex)
Catch ex As Exception
End Try
myLbox.EndUpdate()
myParentForm = GetParentForm(Me)
If myParentForm IsNot Nothing Then
myLbox.Name = "mmmlbox" & Now.Millisecond
If myForm.Visible = False Then
myForm.Font = Me.Font
myLbox.Font = Me.Font
myLbox.Visible = True
myForm.Visible = False
myForm.ControlBox = False
myForm.Text = ""
If First Then
myForm.Width = Me.Width
myForm.Height = 200
End If
First = False
If Not myForm.Controls.Contains(myLbox) Then myForm.Controls.Add(myLbox)
myForm.FormBorderStyle = FormBorderStyle.None
myForm.ShowInTaskbar = False
With myLbox
.Dock = DockStyle.Fill
.SelectionMode = SelectionMode.One
End With
'Frm.Controls.Add(myLbox)
DontHide = True
SuspendFocus = True
myForm.TopMost = True
myForm.FormBorderStyle = Me.myAutoCompleteFormBorder
myForm.BringToFront()
Call MoveDrop()
myForm.Visible = True
myForm.Show()
Call MoveDrop()
HideTimer.Interval = 10
Me.Focus()
SuspendFocus = False
HideTimer.Enabled = True
DontHide = False
Call LoadSelects()
End If
End If
TempLogStop()
End Sub
Sub MoveDrop()
TempLogStart()
Dim Pnt As Point = New Point(Me.Left, Me.Top + Me.Height + 2)
Dim ScreenPnt As Point = Me.PointToScreen(New Point(-2, Me.Height))
'Dim FrmPnt As Point = Frm.PointToClient(ScreenPnt)
If myForm IsNot Nothing Then
myForm.Location = ScreenPnt
'myForm.BringToFront()
'myForm.Focus()
'myLbox.Focus()
'Me.Focus()
End If
TempLogStop()
End Sub
Sub DoHide(ByVal sender As Object, ByVal e As EventArgs)
TempLogStart()
Call HideAuto()
TempLogStop()
End Sub
Private Sub DFocus(Optional ByVal Delay As Integer = 10)
TempLogStart()
FocusTimer.Interval = Delay
FocusTimer.Start()
TempLogStop()
End Sub
Private Sub DoHideAuto()
TempLogStart()
myForm.Hide()
HideTimer.Enabled = False
FocusTimer.Enabled = False
TempLogStop()
End Sub
Private Sub HideAuto()
TempLogStart()
If myForm.Visible AndAlso HasLostFocus() Then
Call DoHideAuto()
End If
TempLogStop()
End Sub
Private Function HasLostFocus() As Boolean
TempLogStart()
Dim Out As Boolean
If Me.myForm Is Nothing OrElse myForm.ActiveControl IsNot Me.myLbox Then
Out = True
End If
If Me.myParentForm Is Nothing OrElse Me.myParentForm.ActiveControl IsNot Me Then
Out = True
End If
TempLogStop()
Return Out
End Function
Private Function GetParentForm(ByVal InCon As Control) As Form
TempLogStart()
Dim TopCon As Control = FindTopParent(InCon)
Dim Out As Form = Nothing
If TypeOf TopCon Is Form Then
Out = CType(TopCon, Form)
End If
TempLogStop()
Return Out
End Function
Private Function FindTopParent(ByVal InCon As Control) As Control
TempLogStart()
Dim Out As Control
If InCon.Parent Is Nothing Then
Out = InCon
Else
Out = FindTopParent(InCon.Parent)
End If
TempLogStop()
Return Out
End Function
Public Class clsAutoCompleteEventArgs
Inherits EventArgs
Private myAutoCompleteList As List(Of String)
Private myCancel As Boolean
Private mySelectedIndex As Integer
Public Property SelectedIndex() As Integer
Get
Return mySelectedIndex
End Get
Set(ByVal value As Integer)
mySelectedIndex = value
End Set
End Property
Public Property Cancel() As Boolean
Get
Return myCancel
End Get
Set(ByVal value As Boolean)
myCancel = value
End Set
End Property
Public Property AutoCompleteList() As List(Of String)
Get
Return myAutoCompleteList
End Get
Set(ByVal value As List(Of String))
myAutoCompleteList = value
End Set
End Property
End Class
Protected Overrides Sub OnKeyUp(ByVal e As System.Windows.Forms.KeyEventArgs)
TempLogStart()
TempLogStop()
MyBase.OnKeyUp(e)
Call ShowOnChar(Chr(e.KeyValue))
End Sub
Private Sub ShowOnChar(ByVal C As String)
TempLogStart()
TempLogStop()
If IsPrintChar(C) Then
Call Me.ShowAutoComplete()
End If
End Sub
Private Function IsPrintChar(ByVal C As Integer) As Boolean
TempLogStart()
TempLogStop()
Return IsPrintChar(Chr(C))
End Function
Private Function IsPrintChar(ByVal C As Byte) As Boolean
TempLogStart()
TempLogStop()
Return IsPrintChar(Chr(C))
End Function
Private Function IsPrintChar(ByVal C As Char) As Boolean
TempLogStart()
TempLogStop()
Return IsPrintChar(C.ToString)
End Function
Private Function IsPrintChar(ByVal C As String) As Boolean
TempLogStart()
If System.Text.RegularExpressions.Regex.IsMatch(C, "[^\t\n\r\f\v]") Then
Return True
Else
Return False
End If
TempLogStop()
End Function
Private Sub clsCustomAutoCompleteTextbox_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.GotFocus
TempLogStart()
If Not Me.SuspendFocus AndAlso Me.myShowAutoCompleteOnFocus AndAlso Me.myForm.Visible = False Then
Call Me.ShowAutoComplete()
End If
TempLogStop()
End Sub
Private Sub clsCustomAutoCompleteTextbox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles Me.KeyDown
TempLogStart()
If Not SelectItem(e.KeyCode) Then
If e.KeyCode = Keys.Up Then
If myLbox.SelectedIndex > 0 Then
Call MoveLBox(myLbox.SelectedIndex - 1)
End If
ElseIf e.KeyCode = Keys.Down Then
Call MoveLBox(myLbox.SelectedIndex + 1)
End If
End If
TempLogStop()
End Sub
Shadows Sub SelectAll()
End Sub
Private Sub MoveLBox(ByVal Index As Integer)
TempLogStart()
Try
If Index > myLbox.Items.Count - 1 Then
Index = myLbox.Items.Count - 1
End If
myLbox.SelectedIndex = Index
Catch ex As Exception
End Try
TempLogStop()
End Sub
Private Sub clsCustomAutoCompleteTextbox_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Leave
TempLogStart()
Call DoHide(sender, e)
TempLogStop()
End Sub
Private Sub clsCustomAutoCompleteTextbox_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.LostFocus
TempLogStart()
Call DoHide(sender, e)
TempLogStop()
End Sub
Private Sub clsCustomAutoCompleteTextbox_Move(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Move
TempLogStart()
Call MoveDrop()
TempLogStop()
End Sub
Private Sub clsCustomAutoCompleteTextbox_ParentChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.ParentChanged
TempLogStart()
myParentForm = GetParentForm(Me)
TempLogStop()
End Sub
Private Sub HideTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles HideTimer.Tick
TempLogStart()
Call MoveDrop()
Call DoHide(sender, e)
Static Cnt As Integer = 0
Cnt += 1
If Cnt > 300 Then
If Not AppHasFocus() Then
Call DoHideAuto()
End If
Cnt = 0
End If
TempLogStop()
End Sub
Public Overrides Property SelectedText() As String
Get
Return MyBase.SelectedText
End Get
Set(ByVal value As String)
MyBase.SelectedText = value
End Set
End Property
Public Overrides Property SelectionLength() As Integer
Get
Return MyBase.SelectionLength
End Get
Set(ByVal value As Integer)
MyBase.SelectionLength = value
End Set
End Property
Private Sub myLbox_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.Click
End Sub
Private Sub myLbox_DoubleClick(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.DoubleClick
End Sub
Private Function SelectItem(Optional ByVal Key As Keys = Keys.None, _
Optional ByVal SingleClick As Boolean = False, _
Optional ByVal DoubleClick As Boolean = False) As Boolean
TempLogStart()
Dim DoSelect As Boolean = True
Dim Meth As SelectOptions
Static LastItem As Integer = -1
Select Case True
Case Me.mySelectionMethods And SelectOptions.OnEnterPress AndAlso Key = Keys.Enter
Meth = SelectOptions.OnEnterPress
Case Me.mySelectionMethods And SelectOptions.OnRightArrow AndAlso Key = Keys.Right
Meth = SelectOptions.OnRightArrow
Case Me.mySelectionMethods And SelectOptions.OnTabPress AndAlso Key = Keys.Tab
Meth = SelectOptions.OnTabPress
Case Me.mySelectionMethods And SelectOptions.OnSingleClick AndAlso SingleClick
Meth = SelectOptions.OnSingleClick
Case Me.mySelectionMethods And SelectOptions.OnDoubleClick AndAlso DoubleClick
Meth = SelectOptions.OnDoubleClick
'Case Me.mySelectionMethods And SelectOptions.OnItemChange AndAlso (LastItem <> myLbox.SelectedIndex)
Case Else
DoSelect = False
End Select
LastItem = myLbox.SelectedIndex
If DoSelect Then
Call DoSelectItem(Meth)
End If
TempLogStop()
Return DoSelect
End Function
Private Sub DoSelectItem(ByVal Method As SelectOptions)
TempLogStart()
If Me.myLbox.Items.Count > 0 AndAlso Me.myLbox.SelectedIndex > -1 Then
Dim Value As String = Me.myLbox.SelectedItem.ToString
Dim Orig As String = Me.Text
Me.Text = Value
If mySelectTextAfterItemSelect Then
Try
Me.SelectionStart = Orig.Length
Me.SelectionLength = Value.Length - Orig.Length
Catch ex As Exception
End Try
Else
'Me.SelectionStart = Me.Text.Length
'Me.SelectionLength = 0
End If
RaiseEvent ItemSelected(Me, New clsItemSelectedEventArgs(Me.myLbox.SelectedIndex, Method, Value))
Call Me.DoHideAuto()
End If
TempLogStop()
End Sub
Public Class clsItemSelectedEventArgs
Private myIndex As Integer
Private myMethod As SelectOptions
Private myItemText As String
Public Property ItemText() As Boolean
Get
Return myItemText
End Get
Set(ByVal value As Boolean)
myItemText = value
End Set
End Property
Public Property Method() As SelectOptions
Get
Return myMethod
End Get
Set(ByVal value As SelectOptions)
myMethod = value
End Set
End Property
Public Property Index() As Integer
Get
Return myIndex
End Get
Set(ByVal value As Integer)
myIndex = value
End Set
End Property
Sub New()
End Sub
Sub New(ByVal Index As Integer, ByVal Method As SelectOptions, ByVal ItemText As String)
myIndex = Index
myMethod = Method
myItemText = ItemText
End Sub
End Class
Private Sub myLbox_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.GotFocus
TempLogStart()
Call DFocus()
TempLogStop()
End Sub
Private Sub myLbox_KeyDown(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles myLbox.KeyDown
TempLogStart()
Call SelectItem(e.KeyCode)
TempLogStop()
End Sub
Private Sub ProcessKeyEvents(ByVal e As KeyEventArgs)
TempLogStart()
Select Case e.KeyCode
Case Is >= Keys.A And e.KeyCode <= Keys.Z
MyBase.OnKeyUp(e)
Case Keys.Back
Case Keys.Enter
Case Keys.Left, Keys.Right, Keys.Up, Keys.Down
Case Is >= Keys.NumPad0 And e.KeyCode <= Keys.NumPad9, Is >= Keys.D0 And e.KeyCode <= Keys.D9
End Select
TempLogStop()
End Sub
Private Sub myLbox_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles myLbox.KeyPress
If IsPrintChar(e.KeyChar) Then
'Me.OnKeyPress(e)
'Call MoveDrop()
End If
TempLogStop()
End Sub
Private Sub myLbox_KeyUp(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyEventArgs) Handles myLbox.KeyUp
If IsPrintChar(e.KeyValue) Then
'Me.OnKeyUp(e)
'Call MoveDrop()
End If
TempLogStop()
End Sub
Private Sub myLbox_LostFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles myLbox.LostFocus
TempLogStart()
Call DoHide(sender, e)
TempLogStop()
End Sub
Private Sub myLbox_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseClick
TempLogStart()
'If e.Button <> Windows.Forms.MouseButtons.None Then
Call SelectItem(SingleClick:=True)
'End If
TempLogStop()
End Sub
Private Sub myLbox_MouseDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseDoubleClick
TempLogStart()
'If e.Button <> Windows.Forms.MouseButtons.None Then
Call SelectItem(DoubleClick:=True)
'End If
TempLogStop()
End Sub
Private Sub myForm_Deactivate(ByVal sender As Object, ByVal e As System.EventArgs) Handles myForm.Deactivate
TempLogStart()
Call TryHideFormWindowsDeactivated()
TempLogStop()
End Sub
Private Sub myParentForm_Deactivate(ByVal sender As Object, ByVal e As System.EventArgs) Handles myParentForm.Deactivate
TempLogStart()
Call TryHideFormWindowsDeactivated()
TempLogStop()
End Sub
Private Sub FocusTimer_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles FocusTimer.Tick
TempLogStart()
Me.Focus()
TempLogStop()
End Sub
Public Sub New()
End Sub
Private Sub myLbox_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles myLbox.MouseDown
myLbox_MouseClick(sender, e)
End Sub
End Class
#End Region
I don't know if this is an option, but, for example you could do something like this:
private void Main_Load(object sender, EventArgs e)
{
DataTable dt = new DataTable();
dt.Columns.Add("colCustomers", typeof(string));
dt.Rows.Add(new object[] { "1 John" });
dt.Rows.Add(new object[] { "2 Kate" });
dt.Rows.Add(new object[] { "3 Jill" });
comboBox1.DataSource = dt.DefaultView; //allows us to filter the results
comboBox1.DisplayMember = "Col1";
}
private void comboBox1_TextChanged(object sender, EventArgs e)
{
if (comboBox1.SelectedIndex == -1)
{
dt.DefaultView.RowFilter = "colCustomers LIKE '%" + comboBox1.Text + "%'";
}
}
Ofcourse, you can also use searching & positioning instead of filtering, but since there's probably many customers I thought it would be better to leave just the customers that match. When the user deletes his entry it should display everyone again. The code could probably benefit from some tweaking to your needs, but you'll have to experiment to come up with what you wanted.
you can use this class :
public partial class MyComboBox : ComboBox
{
private IList<object> collectionList = null;
public MyComboBox()
{
InitializeComponent();
collectionList = new List<object>();
}
public MyComboBox(IContainer container)
: this()
{
container.Add(this);
}
protected override void OnTextUpdate(EventArgs e)
{
try
{
//base.OnTextUpdate(e);
IList<object> values = collectionList
.Where(x => x.ToString().ToLower().Contains(Text.ToLower()))
.ToList();
//Don't use Items.Clear() because the selectionstart resets to Zero
while (Items.Count > 0)
{
Items.RemoveAt(0);
}
this.Items.AddRange(values.ToArray());
this.DroppedDown = true;
Cursor.Current = Cursors.Default;
}
catch(Exception ex)
{
SelectedIndex = -1;
//MessageBox.Show(ex.Message);
}
}
protected override void OnTextChanged(EventArgs e)
{
//base.OnTextChanged(e);
if (this.Text == string.Empty)
{
Items.Clear();
this.Items.AddRange(collectionList.ToArray());
}
}
protected override void OnBindingContextChanged(EventArgs e)
{
base.OnBindingContextChanged(e);
collectionList = this.Items.OfType<object>().ToList();
}
}
Here's my code for a databound combobox (in my case an Access DB). You add a a combobox and listbox to the form. Then, use my code below as a reference as it shows:
- How to update the databound combobox
- Add event handlers such that when you use the arrow keys in the combobox it goes through the results in the listbox.
- Use a timer to limit database queries to only when 500ms has elapsed since last keypress.
I'm sure there are better ways of doing some of this. This code is "works for me". Critiques are appreciated.
#region AutoComplete Organization Box
System.Windows.Forms.Timer mOrganizationTextChangedTimer = null;
void organizationComboBox_TextChanged(object sender, System.EventArgs e)
{
if (mOrganizationTextChangedTimer == null)
{
mOrganizationTextChangedTimer = new System.Windows.Forms.Timer();
mOrganizationTextChangedTimer.Interval = 500;
mOrganizationTextChangedTimer.Tick += new EventHandler(mOrganizationTextChangedTimer_Tick);
}
mOrganizationTextChangedTimer.Enabled = true;
}
void mOrganizationTextChangedTimer_Tick(object sender, EventArgs e)
{
mOrganizationTextChangedTimer.Enabled = false;
UpdateOrganizationNameAutocompleteResults( comboBoxOrganizationName.Text );
}
void UpdateOrganizationNameAutocompleteResults( string pSearchString )
{
listBoxOrganizationAutocompleteResults.Items.Clear();
if (comboBoxOrganizationName.Text.Length == 0)
{
HideOrganizationNameAutocompleteResults();
return;
}
// Added a custom query to search our database and return results that match. The query uses UCase on the columns.
allertDataSet3.OrganizationDataTable orgs = organizationTableAdapter.GetDataByOrganizationNameSearchUCase("%" + pSearchString.ToUpper() + "%", "%" + pSearchString.ToUpper() + "%");
foreach( allertDataSet3.OrganizationRow r in orgs ) {
string longName = r.OrganizationName;
listBoxOrganizationAutocompleteResults.Items.Add(longName);
listBoxOrganizationAutocompleteResults.Visible = true;
listBoxOrganizationAutocompleteResults.BringToFront();
}
// This Code block is needed because once you select an organization, the combobox text changes which forces another search.
// There is only one result from that search so this hides it when the search result equals the already selected combobox.
try {
System.Data.DataRowView drv = (System.Data.DataRowView) comboBoxOrganizationName.SelectedItem;
allertDataSet3.OrganizationRow orgRow = (allertDataSet3.OrganizationRow)drv.Row;
if ( listBoxOrganizationAutocompleteResults.Items.Count == 1 &&
((string)listBoxOrganizationAutocompleteResults.Items[0]).Equals(orgRow.OrganizationName) )
{
HideOrganizationNameAutocompleteResults();
}
}
catch {
// do nothing
}
}
void organizationComboBoxAutocompleteResults_SelectedIndexChanged(object sender, System.EventArgs e)
{
foreach (System.Data.DataRowView drv in comboBoxOrganizationName.Items)
{
Alertus.Allert.allertDataSet3.OrganizationRow orgRow = (Alertus.Allert.allertDataSet3.OrganizationRow)drv.Row;
if (orgRow.OrganizationName.Equals((string) listBoxOrganizationAutocompleteResults.SelectedItem))
{
// Prevents it from searching again.
comboBoxOrganizationName.TextChanged -= organizationComboBox_TextChanged;
comboBoxOrganizationName.SelectedItem = drv;
comboBoxOrganizationName.TextChanged += organizationComboBox_TextChanged;
HideOrganizationNameAutocompleteResults();
return;
}
}
// This is basically an error... it should have found it.
HideOrganizationNameAutocompleteResults();
}
void listBoxOrganizationAutocompleteResults_LostFocus(object sender, System.EventArgs e)
{
HideOrganizationNameAutocompleteResults();
}
void HideOrganizationNameAutocompleteResults()
{
listBoxOrganizationAutocompleteResults.Visible = false;
}
private void listBoxOrganizationAutocompleteResults_MouseClick(object sender, MouseEventArgs e)
{
// When mouse is clicked we assume user made a seletion.
organizationComboBoxAutocompleteResults_SelectedIndexChanged(null, null);
}
/// <summary>
/// Redirects the Arrow keys to update the selected index in the autocomplete list box.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void comboBoxOrganizationName_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Up)
{
if (listBoxOrganizationAutocompleteResults.Items.Count >= 1 && listBoxOrganizationAutocompleteResults.Visible)
{
if (listBoxOrganizationAutocompleteResults.SelectedIndex < 0)
{
listBoxOrganizationAutocompleteResults.SelectedIndex = 0;
}
else
{
listBoxOrganizationAutocompleteResults.SelectedIndex = (listBoxOrganizationAutocompleteResults.SelectedIndex - 1) % listBoxOrganizationAutocompleteResults.Items.Count;
}
}
e.Handled = true;
}
else if (e.KeyCode == Keys.Down)
{
if (listBoxOrganizationAutocompleteResults.Items.Count >= 1 && listBoxOrganizationAutocompleteResults.Visible )
{
if (listBoxOrganizationAutocompleteResults.SelectedIndex < 0)
{
listBoxOrganizationAutocompleteResults.SelectedIndex = 0;
}
else
{
listBoxOrganizationAutocompleteResults.SelectedIndex = (listBoxOrganizationAutocompleteResults.SelectedIndex + 1) % listBoxOrganizationAutocompleteResults.Items.Count;
}
}
e.Handled = true;
}
else if (e.KeyCode == Keys.Enter)
{
e.Handled = true;
if (listBoxOrganizationAutocompleteResults.Visible)
{
organizationComboBoxAutocompleteResults_SelectedIndexChanged(null, null);
}
}
}
#endregion
Designer Code:
//
// comboBoxOrganizationName
//
this.comboBoxOrganizationName.FormattingEnabled = true;
this.comboBoxOrganizationName.Location = new System.Drawing.Point(19, 53);
this.comboBoxOrganizationName.Name = "comboBoxOrganizationName";
this.comboBoxOrganizationName.Size = new System.Drawing.Size(363, 21);
this.comboBoxOrganizationName.TabIndex = 1;
this.comboBoxOrganizationName.SelectedIndexChanged += new System.EventHandler(this.comboBoxOrganizationName_SelectedIndexChanged);
this.comboBoxOrganizationName.Enter += new System.EventHandler(this.comboBoxOrganizationName_Enter);
this.comboBoxOrganizationName.KeyDown += new System.Windows.Forms.KeyEventHandler(this.comboBoxOrganizationName_KeyDown);
this.comboBoxOrganizationName.TextChanged += new System.EventHandler(this.organizationComboBox_TextChanged);**
//
// listBoxOrganizationAutocompleteResults
//
this.listBoxOrganizationAutocompleteResults.FormattingEnabled = true;
this.listBoxOrganizationAutocompleteResults.Location = new System.Drawing.Point(20, 76);
this.listBoxOrganizationAutocompleteResults.Name = "listBox1";
this.listBoxOrganizationAutocompleteResults.Size = new System.Drawing.Size(359, 95);
this.listBoxOrganizationAutocompleteResults.TabIndex = 19;
this.listBoxOrganizationAutocompleteResults.Visible = false;
this.listBoxOrganizationAutocompleteResults.MouseClick += new System.Windows.Forms.MouseEventHandler(this.listBoxOrganizationAutocompleteResults_MouseClick);
this.listBoxOrganizationAutocompleteResults.Leave += new System.EventHandler(this.listBoxOrganizationAutocompleteResults_LostFocus);
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