I've got another issue. My method:
public StudentProfile GetFullStudentProfile(int userID)
{
SqlConnection conn = new SqlConnection(Config.DbConnectionString);
SqlCommand cmd = new SqlCommand("GetFullUserProfile", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add(new SqlParameter("@UserID", SqlDbType.Int));
cmd.Parameters["@UserID"].Value = userID;
StudentProfile sp = null;
try
{
conn.Open();
SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.SingleRow);
if (reader.Read())
{
sp = new StudentProfile((int)reader["UserID"], (string)reader["UserName"], (string)reader["UserFamilyName"], (DateTime)reader["UserBirthDay"], (string)reader["UserTelephone"], (string)reader["UserEmail"], (DateTime)reader["UserRegDate"], (string)reader["UserComment"], (bool)reader["UserActive"]);
}
reader.Close();
}
catch (Exception ex)
{
//lbl.Text = ex.Message;
}
finally
{
conn.Close();
}
return sp;
}
Code in WebUserControl:
protected void ddlStudents_SelectedIndexChanged(object sender, EventArgs e)
{
CatalogAccess ca=new CatalogAccess();
lblEmail.Visible = true;
lblName.Visible = true;
lblTelephone.Visible = true;
HiddenID.Value = ddlStudents.SelectedValue;
lblName.Text = HiddenID.Value;
lblEmail.Text = ca.GetFullStudentProfile(ddlStudents.SelectedIndex).UserEmail;
lblFamilyName.Visible = true;
lblBirth.Visible = true;
ddlStudents.Items.Clear();
PopulateStudentsDDL();
}
When I run the code I am getting exception
Do I understand right that the problem is in method GetFullStudentProfile()? If it's so, how can it be fixed?
I think the problem is:
StudentProfile sp = null;
So it says that variable sp was not filled with data in try block. Is it?
Now adding the StudentProfile.cs class listing:
public class StudentProfile
{ public StudentProfile(int userID, string userName, string userFamilyName, DateTime userBirthDay, string userTelephone, string userEmail,DateTime userRegDate,string userComment,bool userActive) { UserID = userID; UserName = userName; UserFamilyName = userFamilyName; UserBirthDay = userBirthDay; UserTelephone = userTelephone; UserEmail = userEmail; UserRegdate = userRegDate; UserComment = userComment; Use开发者_如何学编程rActive = userActive; }
public int UserID
{
get;
set;
}
public string UserName
{
get;
set;
}
public string UserFamilyName
{
get;
set;
}
public DateTime UserBirthDay
{
get;
set;
}
public string UserTelephone
{
get;
set;
}
public string UserEmail
{
get;
set;
}
public DateTime UserRegdate
{
get;
set;
}
public string UserComment
{
get;
set;
}
public bool UserActive
{
get;
set;
}
}
What exactly is null? I bet GetFullStudentProfile
method returns null.
Yes, that's exactly what happened. The student matching passed ID is not found. I would do the following in your Client code:
StudentProfile sp=ca.GetFullStudentProfile(ddlStudents.SelectedIndex);
lblEmail.Text = sp != null ? sp.UserEmail : string.Empty;
Also i would rewrite the GetFullStudentProfile
method's reader operation to something like this:
conn.Open();
SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.SingleRow);
if (reader.Read())
{
sp = new StudentProfile((int)reader["UserID"], (string)reader["UserName"], (string)reader["UserFamilyName"], (DateTime)reader["UserBirthDay"], (string)reader["UserTelephone"], (string)reader["UserEmail"], (DateTime)reader["UserRegDate"], (string)reader["UserComment"], (bool)reader["UserActive"]);
}
reader.Close();
It's just a face-lift for the routine, looks nicer imho
Also:
HiddenID.Value = ddlStudents.SelectedValue;
lblName.Text = HiddenID.Value;
I noticed in your Autos that the name was set as 1. So I think you actually are meaning to set it as:
lblName.Text = ddlStudents.SelectedValue;
I don't believe that setting the value equal to itself is going to benefit you in any way. Check your database, does the column for UserEmail allow nullables?
Also, in your database, I believe that UserID increments starting at 1, correct? SelectedIndex, I believe, starts at 0. You may need to increment the selectedvalue item by 1.
I just looked at your other question (http://stackoverflow.com/questions/5745820/assign-list-member-to-label) and I feel I have a bit more info here.
If your database doesn't allow nullable types, I would change:
CatalogAccess ca=new CatalogAccess();
lblEmail.Visible = true;
lblName.Visible = true;
lblTelephone.Visible = true;
HiddenID.Value = ddlStudents.SelectedValue;
lblName.Text = HiddenID.Value;
lblEmail.Text = ca.GetFullStudentProfile(ddlStudents.SelectedIndex).UserEmail;
lblFamilyName.Visible = true;
lblBirth.Visible = true;
ddlStudents.Items.Clear();
PopulateStudentsDDL();
to:
CatalogAccess ca=new CatalogAccess();
lblEmail.Visible = true;
lblName.Visible = true;
lblTelephone.Visible = true;
// if your table's ID increments starting at 0, otherwise ddlStudents.SelectedIndex + 1
StudentProfile student = GetFullStudentProfile(ddlStudents.SelectedIndex);
if (student != null)
{
lblName.Text = student.UserName;
lblEmail.Text = student.UserEmail;
//rest of the labels going here (I only see Name and Email)
}
...
You also may consider putting your calls making labels visible inside of the sp != null conditional so that only if a valid person displays will it actually display those labels. Otherwise keep them before it.
Otherwise I would do similar to Dimitri and say
lblName.Text = student.UserName != null ? student.UserName : String.Empty;
lblEmail.Text = student.UserEmail != null ? student.UserEmail : String.Empty;
// etc.
If nullables are possible, the student object could actually be assigned to, but the properties may not which may cause your application problems at runtime.
Ok. I made a new method:
public UserDetails GetUser(int userID)
{
SqlConnection conn = new SqlConnection(Config.DbConnectionString);
SqlCommand cmd = new SqlCommand("GetFullUserProfile", conn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add(new SqlParameter("@UserID", SqlDbType.Int, 4));
cmd.Parameters["@UserID"].Value = userID;
try
{
conn.Open();
SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.SingleRow);
// Check if the query returned a record.
if (!reader.HasRows) return null;
// Get the first row.
reader.Read();
UserDetails emp = new UserDetails((int)reader["UserID"], (string)reader["UserName"], (string)reader["UserFamilyName"], (DateTime)reader["UserBirthDate"], (string)reader["UserTelephone"], (string)reader["UserEmail"], (DateTime)reader["RegDate"], (string)reader["UserComment"], (int)reader["UserActive"]);
reader.Close();
return emp;
}
catch (SqlException err)
{
throw new ApplicationException("Data error.");
}
finally
{
conn.Close();
}
}
New Class:
using System;
public class UserDetails
{
public UserDetails(int userID, string userName, string userFamilyName, DateTime userBirthDate, string userTelephone, string userEmail, DateTime regDate, string userComment, int userActive)
{
UserID = userID;
UserName = userName;
UserFamilyName = userFamilyName;
UserBirthDay = userBirthDate;
UserTelephone = userTelephone;
UserEmail = userEmail;
RegDate = regDate;
UserComment = userComment;
userActive = UserActive;
}
public int UserID
{ get; set; }
public string UserName
{ get; set; }
public string UserFamilyName
{ get; set; }
public DateTime UserBirthDay
{ get; set; }
public string UserTelephone
{ get; set; }
public string UserEmail
{ get; set; }
public DateTime RegDate
{ get; set; }
public string UserComment
{ get; set; }
public int UserActive
{ get; set; }
}
After that in my back-code of WebUserControl:
UserDetails ud = ca.GetUser(24);
//HiddenID.Value = String.Format(ud.UserID);
lblName.Text = ud.UserName;
lblEmail.Text = ud.UserEmail;
lblFamilyName.Text = ud.UserFamilyName;
lblBirth.Text=String.Format("{0:dd/MM/yyy}",ud.UserBirthDay);
lblTelephone.Text = ud.UserTelephone;
And got the method worked. So, this stage is ready. Thanks to everybody who helped me. Thread is closed.
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