Crashing When textbox text updating on TextChanged Event for Non English Keyboard

Question

Hi Team,

When Typing something on the TextBox which has following code snippet on Text Changed that causes a crashing when keyboard is non English (Japanses/Chinese)

private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
{
textBox.TextChanged -= TextBox_TextChanged;
if(!double.TryParse(textBox.Text,out double result))
{
textBox.Text = "8";
}
textBox.TextChanged += TextBox_TextChanged;

    }

Please let me know why this is happening.

Sincerely,
Jabir E

Answer 1

I test you code and the app crashed with the error:The error code is 0x80131623. This error may be a bug in the CLR or in the unsafe..... The reason for this error is that a large number of TextBox_TextChanged events were triggered which cause memory issue. You can try the below code and input as you did in the question said.

 private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
        {
            //add a breakpoint here.
        }

You will meet the same error, so you need to be careful to use TextBox_TextChanged event. If you want to do limit the TextBox for typing, you can use a DependencyProperty as the backing store for Input Limit. Looking like this:

public static readonly DependencyProperty InputLimitProperty =
            DependencyProperty.RegisterAttached("InputLimit", typeof(bool), typeof(TextBoxExtension), new PropertyMetadata(false, InputLimitChanged));