仅当用户在C＃wpf中更改组合框的选择时，才如何触发selectionChange事件？

Question

I would like to know how to trigger the selectionChange event of a combobox only when the user himself change the selection of the list. (Avoid other cases) I found a solution here but I have some errors. Could you help me?

https://msdn.microsoft.com/en-us/library/system.windows.forms.combobox.selectionchangecommitted(v=vs.110).aspx

I added System.Windows.Forms in my .cs file and it says there is an ambiguity beetween 'System.Windows.Controls.ComboBox' and 'System.Windows.Forms.ComboBox' with the first line of the code below.

I dont know how to cast my sender into a comboBox.

ComboBox senderComboBox = (ComboBox)sender;

        if (senderComboBox.SelectionLength > 0)
        {
            //code here
        }

Thanks for help!

Answer 1

You are trying to reference WinForms ComboBox and not WPF ComboBox . You can listen to SelectionChanged event of the control to know when user changes the selection.

A sample code from dotnetperls

XAML

<ComboBox
    HorizontalAlignment="Left"
    Margin="10,10,0,0"
    VerticalAlignment="Top"
    Width="120"
    Loaded="ComboBox_Loaded"
    SelectionChanged="ComboBox_SelectionChanged"/>

CS File

private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
    // ... Get the ComboBox.
    var comboBox = sender as ComboBox;

    // ... Set SelectedItem as Window Title.
    string value = comboBox.SelectedItem as string;
    this.Title = "Selected: " + value;
}

Answer 2

This sort of approach worked for me - XAML ComboBox SelectionChanged Fires OnLoad

Basically only wire-up the ComboBox_SelectionChanged event after the form has loaded - this will get you around the programmatic change that will fire onload. Beyond that I'm not sure. It might be that you need to use a different event, but I haven't looked into this.