C# - Enabling multiple textboxes in a loop

Question

I'm writing a WPF program, and it involves someone typing in a number, and enabling a corresponding number of text boxes. Currently I have a system that checks every single text box such as

private void navnumbox_TextChanged(object sender, TextChangedEventArgs e)
{
    try
    {
        if (Int32.Parse(navnumbox.Text) > 0)
        {
            One.IsEnabled = true;
        }

        if (Int32.Parse(navnumbox.Text) > 1)
        {
            Two.IsEnabled = true;
        }
    }
}

I want to put this into a loop, and I'm think that I may need to store One and Two in an array, but I have tried but I don't know how to access them

Answer 1

Maybe you could try something like this (I wasn't able to test it sorry).

private void navnumbox_TextChanged(object sender, TextChangedEventArgs e)
{
    var textBoxesMap = new Dictionary<int,TextBox>()
    {
        {1, One},
        {2, Two}
        // etc
    };

    try
    {
        int number = int.Parse(navnumbox.Text)
        foreach(var item in textBoxesMap)
        {
            if(item.Key <= number)
            {
                item.Value.IsEnabled = true;
            }
        }
    }
}

And you can obviously place the map somewhere else. An alternative (and better) approach to this would be to use XAML - there is another answer on this question that demonstrates how to do so.

Answer 2

I think the better approach is to use Converter for Visibility property of the TextBoxes One and Two by ElementBinding to the navnumbox Path=Text.

I your case you will need separate converters for TextBox.Enable for TextBoxes One and Two.

Here XAML for the Window:

<Window x:Class="WpfApplication2.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:wpfApplication2="clr-namespace:WpfApplication2"
        Title="MainWindow"
        Height="350"
        Width="525">
    <Window.Resources>
        <wpfApplication2:MyConverter x:Key="MyConverter"></wpfApplication2:MyConverter>
    </Window.Resources>
    <Grid>
        <StackPanel>
            <TextBox x:Name="MyText"></TextBox>
            <TextBox IsEnabled="{Binding ElementName=MyText, Path=Text, Converter={StaticResource MyConverter}}"></TextBox>
        </StackPanel>
    </Grid>
</Window>

Here implementation of the Converter for TexBox "One"

public class MyConverter
        : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            string myValue = value as string;
            int result = 0;
            if (myValue != null)
            {
                int.TryParse(myValue,out result);
            }

            return result > 0;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            // not relevant for your application
            throw new NotImplementedException();
        }
    }