c# - (int)object parsing gives an "Object reference not set to an instance of an object" exception

Question

This question already has answers here: question from:https://stackoverflow.com/questions/65874312/intobject-parsing-gives-an-object-reference-not-set-to-an-instance-of-an-obje

Answer 1

I bet if you check the value of returnObject, it will be NULL:

using (var con = new SqlConnection(Config.ConnectionString))
{
     object returnedObject = con.ExecuteScalar("spUser_getUBID",
                                               new { name = name, pass = PassHash },
                                               null, null,
                                              commandType: CommandType.StoredProcedure);
    // what value do you get here, in "returnedObject" ?? 
    if (returnedObject != null)
    {
        return (int)returnedObject;
    }
}

ALWAYS check your returned values for null - don't just blindly assume they're ok - many times they're not OK ! Just typecasting using (int) without a NULL check is bound to cause exceptions .....