“Specified cast is not valid” error in C# windows forms program

Question

I\'m having a \"Specified cast is not valid\" error. Windows form application in C#. I\'m trying to retrieve a value from a table. The value is either a smallint, or a numer

Answer 1

Since you said that you know what the value should be because you created the database... Can you check that rdr["quantity"] has a value then run a try parse on it?

if(rdr["quantity"] != null) {
    int? number = null;
    if(int.TryParse(rdr["quantity"].ToString(), out number)) {
        Console.WriteLine("Hurray, I have an int. Up vote Coov!");
    }
}