How to get if a string is a number in T-SQL

Question

Is there an easy way to get if string is an integer number (consists only of digits) in MS SQL 2005?

Thank you for your help.

Answer 1

See this:

CREATE Function dbo.IsInteger(@Value VarChar(18))
Returns Bit
As 
Begin

  Return IsNull(
 (Select Case When CharIndex('.', @Value) > 0 
              Then Case When Convert(int, ParseName(@Value, 1)) <> 0
                        Then 0
                        Else 1
                        End
              Else 1
              End
      Where IsNumeric(@Value + 'e0') = 1), 0)   

End