Convert String to Title Case

CREATE FUNCTION ToTitleCaseFunc (@InputString NVARCHAR(MAX) )
RETURNS NVARCHAR(MAX)
AS
BEGIN
	DECLARE @Index INT
	DECLARE @Char CHAR(1)
	DECLARE @OutputString NVARCHAR(MAX)
	
	SET @OutputString = LOWER(@InputString)
	SET @Index = 2
	SET @OutputString =	STUFF(@OutputString, 1, 1,UPPER(SUBSTRING(@InputString,1,1)))
	
	WHILE @Index <= LEN(@InputString)
	BEGIN
		SET @Char = SUBSTRING(@InputString, @Index, 1)
		IF @Char IN (' ', ';', ':', '!', '?', ',', '.', '_', '-', '/', '&','''','(')
		IF @Index + 1 <= LEN(@InputString)
		BEGIN
			IF @Char != '''' OR	UPPER(SUBSTRING(@InputString, @Index + 1, 1)) != 'S'
			   SET @OutputString =	STUFF(@OutputString, @Index + 1, 1,UPPER(SUBSTRING(@InputString, @Index + 1, 1)))
		END
		
		SET @Index = @Index + 1
	END
	
	RETURN ISNULL(@OutputString,'')
END

SELECT dbo.ToTitleCaseFunc('HELLO,HOW ARE YOU?')

Hello,How Are You?