The parameterized query which was not supplied

Question

I keep getting this error :

The parameterized query \'(@AdminEmail nvarchar(4000),@AdminPassword nvarchar(4000))SELECT\' expects the parameter \'@A

Answer 1

Your @AdminEmail variable EMail is null. You cannot pass a null on a required parameter. Use DBNull.Value.

When using null, you are informing Sql Server that you are omitting the parameter. This can be useful for an optional parameter with a default value, but causes an error for a required parameter.

I recommend that you use always use a utility function when passing a value to a command parameter.

For example:

public static object GetDataValue(object value)
{
   if(value == null)
   {
       return DBNull.Value;
   }

   return value;
}

and then use

cmd.Parameters.AddWithValue("@AdminEmail", GetDataValue(EMail))