How to add a focus to an editable ComboBox in WPF

Question

I am using an editable ComboBox in wpf but when i try to set focus from C# code, it is only shows selection. but i want to go for edit option (cursor should display for user

Answer 1

You might try deriving from ComboBox and access the internal TextBox, like this:

public class MyComboBox : ComboBox
{
    TextBox _textBox;

    public override void OnApplyTemplate()
    {
        base.OnApplyTemplate();

        _textBox = Template.FindName("PART_EditableTextBox", this) as TextBox;
        if (_textBox != null)
        {
            _textBox.GotKeyboardFocus += _textBox_GotFocus;
            this.Unloaded += MyComboBox_Unloaded;
        }
    }

    void MyComboBox_Unloaded(object sender, System.Windows.RoutedEventArgs e)
    {
        _textBox.GotKeyboardFocus -= _textBox_GotFocus;
        this.Unloaded -= MyComboBox_Unloaded;
    }

    void _textBox_GotFocus(object sender, System.Windows.RoutedEventArgs e)
    {
        _textBox.Select(_textBox.Text.Length, 0); // set caret to end of text
    }

}

In your code you would use it like this:

    ...
        
            Alpha
            Beta
            Gamma
        
    ...

This solution slightly dangerous, however, because in upcoming versions of WPF, Microsoft might decide also to add a GotKeyboardFocus event handler (or similar event handlers), which might get in conflict in with the event handler in MyComboBox.