Programmatically discard changes in DataForm

Question

I have a DataForm from System.Windows.Controls.Data.DataForm.Toolkit and I need to programmatically get the same result as after clicking Cancel on this DataForm.

I need that because this DataForm is in ChildWindow, and if I change something in DataForm and I close a ChildWindow, then changes will be commited. This shouldn't work in that way. When I close ChildWindow I want to discard all changes the same as after clicking Cancel Button.

I've tried

protected override void OnClosing(System.ComponentModel.CancelEventArgs e)
{
    dfColumnInfo.CancelEdit();

    base.OnClosing(e);
}

but it doesn't work.

Thank you in advance.

bugfinder suggested to add a code which saves changes. There is no such thing, because childWindow has an editedObject as a DataContext

childWindow.DataContext = table;
childWindow.MyDataForm.DataContext = table.Items;
childWindow.Show();

I don't know how how, but Cancel button of DataForm reverts all changes which I've done in DataForm, which is a great think. But how to get the same effect by using some other button of childWindow, or just by closing childWindow?

Can you show how and when you call your saving code - its likely its done before you get to the onclosing — BugFinder, Apr 04 '12 at 12:44

score 0 · Answer 1 · edited Apr 10 '12 at 19:14

I searched for you, and found some useful stuff here: http://forums.silverlight.net/t/112449.aspx/1

Then tested like this:

void dform_EditEnded(object sender, DataFormEditEndedEventArgs e)
{
    if (e.EditAction != DataFormEditAction.Commit)
    {
        (dform.CurrentItem as MyEntity).RejectChanges();
        return;
    }
}

To achieve this goal the MyEntity must be public as I coded its partial below. I'm sharing word from silverlightnet forum "To be able to call RejectChanges (which is a protected method of the System.Windows.Ria.Entity class, we have to make it public"

public partial class MyEntity:Entity
{
   public void RejectChanges()
   {
       if (HasChanges)
           base.RejectChanges();
   }
}

Hope this helps.

Programmatically discard changes in DataForm

1 Answers1