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disable textbox in datalist

Posted on 2004-10-19
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Last Modified: 2008-02-01
Dear all,

I have bound a datalist to some table in a database. Everything works fine; I can delete, edit, and update a record. I am just wondering whether it is possible to disable a textbox defined within the <EditItemTemplate> environment like this:
<EditItemTemplate>

...
   <asp:DropDownList Runat="server" ID = "unit" DataSource = '<%# getValues( "unit" ) %>' DataTextField = "unit_name" DataValueField = "unit_uid" />
...

</EditItemTemplate>

I can 'access' the value of the dropdownlist in my OnUpdate( Object source, DataListCommandEventArgs e ) method like this:

( (DropDownList) (e.Item.FindControl( "unit" )) ).SelectedItem.Value

Unfortunately, I cannot do something like this:

public void OnEdit( Object source, DataListCommandEventArgs e )
{
      variable_details_datalist.EditItemIndex = e.Item.ItemIndex;

      …

      ( (DropDownList) (e.Item.FindControl( "unit" )) ).Enabled = false;

      …
}
            

I obtain a System.NullReferenceException. I don't understand why, as all the EditItems must surely be initialised when the OnEdit handler is called?

Looking forward to your reply.

Many thanks in advance.



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Comment
Question by:csetzkorn
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2 Comments
 
LVL 18

Accepted Solution

by:
tusharashah earned 250 total points
ID: 12348736
Modify your OnEdit like following:

----------------------------------------------------------------------------------------------------------------
public void OnEdit( Object source, DataListCommandEventArgs e )
{
     variable_details_datalist.EditItemIndex = e.Item.ItemIndex;

     …
      switch( e.Item.ItemType )
      {
      case ListItemType.Item:
      //case ListItemType.AlternatingItem:
                      ( (DropDownList) (e.Item.FindControl( "unit" )) ).Enabled = false;
                 break;
                }

     …
}

----------------------------------------------------------------------------------------------------------------

-tushar
0
 

Author Comment

by:csetzkorn
ID: 12349227
I actually had to look for:

if( e.Item.ItemType ==  ListItemType.EditItem )

Still you comment has helped. Thanks.
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