public static string TrimToLength(
this string s, int maxLength, TrimPosition position = TrimPosition.End)
{
if (s == null || s.Length <= maxLength)
{
return(s);
}
if (maxLength <= 0)
{
return(string.Empty);
}
var length = maxLength - 1;
switch (position)
{
case TrimPosition.End:
return(s.Substring(0, length) + "…");
case TrimPosition.Start:
return("…" + s.Substring(s.Length - length, length));
case TrimPosition.Middle:
int suffix = length / 2;
int prefix = length - suffix;
return(s.Substring(0, prefix) + "…" + s.Substring(s.Length - suffix, suffix));
default:
throw new ArgumentOutOfRangeException(nameof(position), position, null);
}
}
public void TrimToLength(string input, int maxLength, TrimPosition position, string expected)
{
Assert.Equal(expected, input.TrimToLength(maxLength, position));
Assert.Equal(expected, StringExtensions.TrimToLength(input, maxLength, position));
}
