NullRefererenceException
    

    foreach (string line in assigment_lines)
        {
            chars.AddRange(line.Split('=')); // Object reference not set to an instance of object.
        }
       string[] strArray = chars.ToArray();


My program give me Null Reference Exception in above code what a problem ?
NullRefererenceException
===

    

    foreach (string line in assigment_lines)
        {
            chars.AddRange(line.Split('=')); // Object reference not set to an instance of object.
        }
       string[] strArray = chars.ToArray();


My program give me Null Reference Exception in above code what a problem ?