I'm using BindingSource.Find() to return to the user's position after refreshing a DataGridView. I use BindingSource.Find() and a RowID as the DataColumn I'm searching on. Unfortuna开发者_StackOverflowtely, Oracle can return two RowIDs that differ only in their case.
BindingSource.Find() returns the first match regardless of case.
Looking at the MSDN docs:
public int Find(string propertyName, Object key)
it says that the propertyName comparison is case-insensitive, but does not mention whether the key comparison is.
Does anyone know how to make BindingSource.Find case sensitive?
For a DataView
all you should need to do is set the CaseSensitive
property of the parent DataTable
to true. I just quickly prototyped that with the following code and it works fine:
public Form1()
{
InitializeComponent();
DataSet set1 = new DataSet();
// Some xml data to populate the DataSet with.
string testXml =
"<?xml version='1.0' encoding='UTF-8'?>" +
"<numbers>" +
"<number><name>one</name></number>" +
"<number><name>two</name></number>" +
"<number><name>Two</name></number>" +
"<number><name>three</name></number>" +
"</numbers>";
// Read the xml.
StringReader reader = new StringReader(testXml);
set1.ReadXml(reader);
// Get a DataView of the table contained in the dataset.
DataTableCollection tables = set1.Tables;
// Set the CaseSensetive property
tables[0].CaseSensitive = true;
DataView view1 = new DataView(tables[0]);
// Create a DataGridView control and add it to the form.
dataGridView1.AutoGenerateColumns = true;
// Create a BindingSource and set its DataSource property to
// the DataView.
BindingSource source1 = new BindingSource();
source1.DataSource = view1;
// Set the data source for the DataGridView.
dataGridView1.DataSource = source1;
// Set the Position property to the results of the Find method.
int itemFound = source1.Find("name", "Two");
source1.Position = itemFound;
}
For other types of IBindingList you need, as the docs say, an underlying list that implements a Find which is case sensitive. For completeness I have shown the code to do this below:
public Form1()
{
InitializeComponent();
// This uses my CaseSensitiveBindingList which I have code for later
BindingList<DGVItems> source = new CaseSensitiveBindingList<DGVItems>()
{
new DGVItems { Number = "one" },
new DGVItems{Number = "two"},
new DGVItems{Number = "Two"}
};
BindingSource bindingSource = new BindingSource();
bindingSource.DataSource = source;
dataGridView1.DataSource = bindingSource;
var index = bindingSource.Find("Number", "Two");
// Index is 2 (third item) as desired.
MessageBox.Show(number.ToString());
}
public class DGVItems
{
public string Number { get; set; }
}
And the code for the CaseSensitiveBindingList is:
public class CaseInsensitiveBindingList<T> : BindingList<T>
{
protected override int FindCore(PropertyDescriptor prop, object key)
{
string stringKey = key as string;
bool keyIsString = stringKey != null;
for (int i = 0; i < Count; ++i)
{
if (keyIsString && prop.PropertyType.IsAssignableFrom(typeof(string)))
{
if (stringKey.Equals(prop.GetValue(Items[i]).ToString(), StringComparison.CurrentCulture))
return i;
}
else
{
if (key.Equals(prop.GetValue(Items[i])))
return i;
}
}
return -1;
}
}
That code could almost certainly be improved but shows the general concept.
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