c# - There is no argument given that corresponds to the required formal parameter - .NET Error

Question

I have been refactoring one of my old MSSQL Connection helper library and I got the following error:

Error CS7036 There is no argument given that corresponds to the required formal parameter 'errorMsg' of 'ErrorEventArg.ErrorEventArg(string, string)' MSSQLTest C:UsersAdministratorDesktopMSSQLTestMSSQLTestMSSQLConnection.cs 61

This is my code so far:

MSSQLConnection.cs

using System;
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Threading;

namespace MSSQLTest
{
    public class ErrorEventArg : EventArgs
    {
        public string ErrorMsg { get; set; }
        public string LastQuery { get; set; }

        public ErrorEventArg(string errorMsg, string lastQuery)
        {
            ErrorMsg = errorMsg;
            LastQuery = lastQuery;
        }
    }

    public class MSSQLConnection
    {
        /// <summary>
        /// Private class objects.
        /// </summary>
        private SqlConnection sqlConnection;
        private int sqlCommandTimeout;
        private string lastQuery = string.Empty;

        /// <summary>
        /// Public event related objects & handler.
        /// </summary>
        public event ErrorHandler OnError;
        public delegate void ErrorHandler(MSSQLConnection sender, ErrorEventArg e);

        /// <summary>
        /// Class constructor.
        /// </summary>
        /// <param name="sqlConnection"></param>
        /// <param name="sqlCommandTimeout"></param>
        public MSSQLConnection(SqlConnection sqlConnection, Int32 sqlCommandTimeout = 120)
        {
            if (null == sqlConnection)
                throw new Exception("Invalid MSSQL Database Conection Handle");

            if (sqlConnection.State != System.Data.ConnectionState.Open)
                throw new Exception("MSSQL Database Connection Is Not Open");

            this.sqlConnection = sqlConnection;
            this.sqlCommandTimeout = sqlCommandTimeout;
        }

        /// <summary>
        /// Helper method to emit a database error to event subscribers.
        /// </summary>
        /// <param name="errorMsg"></param>
        internal void EmitError(String errorMsg)
        {
            var errorDelegate = OnError;
            if (errorDelegate != null)
            {
                errorDelegate(this, new ErrorEventArg() // Line #61
                {
                    ErrorMsg = errorMsg,
                    LastQuery = lastQuery
                });
            }
        }
        
        /// rest of the code snipped
    }
}

What does this error means & how do I fix it? I've not seen this error before...

Answer 1

In the constructor of

public class ErrorEventArg : EventArgs

you have to add "base" as follows:

public ErrorEventArg(string errorMsg, string lastQuery) : base (string errorMsg, string lastQuery)
{
    ErrorMsg = errorMsg;
    LastQuery = lastQuery;
}