SQL Query says a parameter is not supplied, but is added to the SqlCommand object

Question

I have a stored procedure that has a parameter called UserName and in my code behind I have a SqlCommand object that I add the parameters to with the Add method. But for som

Answer 1

You will get this exception if the value of your 'userName' variable is null

If null is valid, then pass 'DBNull.Value' to the db instead:

command1.Parameters.Add(new SqlParameter("@UserName", (userName ?? DBNull.Value));