String splitting/tokenizing using T-SQL user defined function.

There is a little inconsistence in this function, because the @Tokens Elements and the @Delimiter parameter are of data type NVARCHAR (=Unicode) while the @String parameter is of data type VARCHAR (=ANSI). If the @String parameter can be Unicode, it must be declared as NVARCHAR. If the @String parameter never can be Unicode, there is no need to declare the @Delimiter parameter or the Tokens as NVARCHAR.
It is posssible that the @Delimiter parameter can content more than one character. I believe, a possible length of 10 characters is enough. The function can look like this:

CREATE FUNCTION dbo.Split (@String NVARCHAR(8000), @Delimiter NVARCHAR(10)) 
RETURNS @Tokens table 
(
Token NVARCHAR(255)
) 
AS 
BEGIN
  WHILE (CHARINDEX(@Delimiter,@String)>0)
   BEGIN 
    INSERT INTO @Tokens (Token) VALUES (LTRIM(RTRIM(SUBSTRING(@String,1,CHARINDEX(@Delimiter,@String)-1))))
    SET @String = SUBSTRING(@String,
    CHARINDEX(@Delimiter,@String)+LEN(@Delimiter),LEN(@String))
   END 
INSERT INTO @Tokens (Token) VALUES (LTRIM(RTRIM(@String)))
RETURN
END
GO

A remaining TODO is to add the ability to handle brackets or quotation marks.