Question

I want to override the Tostring() method for changing some characters. Is it possible? If yes, How can I do this?

Answer 1

As per your question, to change some characters in the ToString implementation, you need to call the existing ToString method by using the base keyword:

public override string ToString()
{
    return base.ToString().Replace("something", "another thing");
}

Note that if you forget the base keyword it will call itself repeatedly until you get a StackOverflowException.