Split Function in Sql Server

Input: 

Row Data:  100,200,300,4000

SplitOn : ','

Output as Table

-----------------

Id      Data

-----------

1        100

2        200

3        300

4        4000

ALTER FUNCTION [dbo].[Split]
(
    @RowData nvarchar(2000),
    @SplitOn nvarchar(5)
) 
RETURNS @RtnValue table
(
    Id int identity(1,1),
    Data nvarchar(100)
)
AS 
BEGIN
    Declare @Cnt int
    Set @Cnt = 1


    While (Charindex(@SplitOn,@RowData)>0)
    Begin
        Insert Into @RtnValue (data)
        Select
            Data = ltrim(rtrim(Substring(@RowData,1,Charindex(@SplitOn,@RowData)-1)))


        Set @RowData = Substring(@RowData,Charindex(@SplitOn,@RowData)+1,len(@RowData))
        Set @Cnt = @Cnt + 1
    End
   
    Insert Into @RtnValue (data)
    Select Data = ltrim(rtrim(@RowData))


    Return
END