String - IsLowSurrogate

Indicates whether the object at the specified position in a string is a low surrogate.

Try it

public static void Main()
{
    string input = new String(new char[] { 'a', '\uD800', '\uDC00', 'z' });

    Console.WriteLine("Is each of the following characters a low surrogate?");
	
    for (int i = 0; i < input.Length; i++)
    {
		// C# Extension Method: String - IsLowSurrogate
		var result = input.IsLowSurrogate(i);
		
        Console.WriteLine("input[{0}] = {1} ", i, result);
    }
}

View Source
using System;

public static partial class Extensions
{
    /// <summary>
    ///     Indicates whether the  object at the specified position in a string is a low surrogate.
    /// </summary>
    /// <param name="s">A string.</param>
    /// <param name="index">The position of the character to evaluate in .</param>
    /// <returns>
    ///     true if the numeric value of the specified character in the  parameter ranges from U+DC00 through U+DFFF;
    ///     otherwise, false.
    /// </returns>
    public static Boolean IsLowSurrogate(this String s, Int32 index)
    {
        return Char.IsLowSurrogate(s, index);
    }
}