WPF - C# Desktop App - Condition, if textbox integer value is 0 than background red and content should be empty.

Question

Hello,
the goal is.
If the value == 0 then backgroundcolor red and empty not zero.

Can I use a converter to handle two conditions?

My idea was via Trigger, but it is not work. Why?

Answer 1

Hi Markus,
you can use Converter.

  public class ViewModel  
  {  
    public int Value { get; set; } = 0;  
  }  
  public class TextBoxConverter : IValueConverter  
  {  
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)  
    {  
      if (targetType == typeof(Brush))  
        return (value.GetType() == typeof(int) && (int)value == 0) ? Brushes.Red : Brushes.White;  
      return (targetType == typeof(string) && (int)value == 0) ? "" : value.ToString();  
    }  
  
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) =>  
      (value == null || string.IsNullOrEmpty(value.ToString())) ? 0: value;  
  }  

Answer 2

You can try the below style for the TextBox:

Answer 3

I think the solution is, for each property I can use a converter.
How is your opinion?