As COMMA is a delimeter for Parameters to procedures, I would suggest you not to pass comma in the @strIDs. This could be worked around in a way that you pass something else in place of COMMA and then within the procedure, convert that somethingelse back to comma.
Eg: From frontend, once the user selects the customers, replace all the comma with something like COLON.
'Not sure what frontend that you use. If that is ASP, then use
strSql = "Execute GetCustomer @strIDs='" & Replace(strSelectedCustomer, ",", ":") & "'"
So that the @strIDs would contain '1:2:3:4:6'.
Then within you procedure use the same replace function to convert those COLONs back to comma.
Create Procedure GetCustomer @strIDs varchar(100) as
Select @strIDs=Replace(@strIDs, ':', ',')
Select * from mastCustomer where ID in (@strIDs)
-- Here the @strIDs would be converted back to '1,2,3,4,6'
-- Also you are missing ()s around @strIDs.
This should be what you are looking for.
Hope that helps.
- Vijay G
Strive for Perfection