/// <summary>
/// All Bindings must be equal to the specified value in the ConverterParameter string before the "?" to return
/// the value after the last "?". else value after ":" is returned
///
/// SAMPLE:
/// <TextBlock.Visibility>
/// <MultiBinding Converter = "{converterHelperSample:IsEqualConverter}"
/// ConverterParameter="a?Visible:Collapsed">
/// <Binding ElementName = "ReasonTextBox"
/// Path="Text" />
/// <Binding ElementName = "TestComboBox"
/// Path="Text" />
/// </MultiBinding>
/// </TextBlock.Visibility>
/// </summary>
/// <param name="values">The value produced by the binding source.</param>
/// <param name="targetType">The type of the binding target property.</param>
/// <param name="parameter">The converter parameter to use.</param>
/// <param name="culture">The culture to use in the converter.</param>
/// <returns>
/// A converted value. If the method returns null, the valid null value is used.
/// </returns>
public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
var parameterString = parameter.ToString();
bool isTrue = false;
if (parameterString.Contains("?"))
{
var compareValue = parameterString.Substring(0, parameterString.IndexOf("?", StringComparison.Ordinal));
isTrue = values.All(i => i?.ToString() == compareValue);
}
else
{
isTrue = values.Skip(1).All(i => i?.ToString() == values[0]?.ToString());
}
return(ConverterHelper.Result <bool?>(isTrue, i => i, targetType, parameter));
}