/// <inheritdoc/>
public override object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
// We get the length first to always throw an exception if the parameter in incorrect
int length;
try
{
length = ConverterHelper.ConvertToInt32(parameter, culture);
if (length == 0)
{
throw new Exception();
}
}
catch (Exception)
{
throw new FormatException("The parameter must be convertible to a non-null integer.");
}
if (value == null)
{
return(null);
}
var addEllipsis = length >= 0;
length = Math.Abs(length);
var str = value.ToString();
return(str.Length > length?str.Substring(0, length) + (addEllipsis ? "..." : "") : str);
}
/// <inheritdoc/>
public override object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
try
{
var charValue = ConverterHelper.ConvertToChar(ConverterHelper.ConvertToInt32(value, culture), culture);
return(charValue);
}
catch (Exception)
{
return(default(char));
}
}
/// <inheritdoc/>
public override object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
var collection = (IList)parameter;
if (collection == null)
{
return(null);
}
var index = ConverterHelper.ConvertToInt32(value ?? -1, culture);
if (index < 0 || index >= collection.Count)
{
return(null);
}
return(collection[index]);
}
/// <inheritdoc/>
public override object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
var unicodeValue = ConverterHelper.ConvertToInt32(value, culture);
return(unicodeValue);
}
