Typecasting in C#

Question

What is type casting, what\'s the use of it? How does it work?

Answer 1

Also, if you're explicitly casting, you can take advantage of pattern matching. If you have an object:

object aObject = "My string value";

You can safely cast the object as a string in a single line:

if (aObject is string aString)
{
    Console.WriteLine("aString = " + aString)
    // Output: "aString = My string value"
}

Using this, along with an inverted if statement, you can safely cast types, and fail out early if need be:

public void Conversion(object objA, object objB)
{
    // Fail out early if the objects provided are not the correct type, or are null
    if (!(objA is string str) || !(objB is int num)) { return; }

    // Now, you have `str` and `num` that are safely cast, non-null variables
    // all while maintaining the same scope as your Conversion method
    Console.WriteLine("str.Length is " + str.Length);
    Console.WriteLine("num is " + num);
}