Sln.Mesnac.PayCalculationSystem/SlnMesnac.WPF/UserControls/FirstItemVisibilityConverter.cs

using System;
using System.Globalization;
using System.Windows;
using System.Windows.Data;

public class FirstItemVisibilityConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var items = parameter as System.Collections.IList;

        if (items != null && items.Count > 0)
        {
            int index = items.IndexOf(value);
            return index == 0 ? Visibility.Visible : Visibility.Collapsed;
        }

        return Visibility.Collapsed;
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}