c# - Casting to string versus calling ToString

Question

object obj = "Hello";
string str1 = (string)obj;
string str2 = obj.ToString();

What is the difference between (string)obj and obj.ToString()?

Answer 1

• (string)obj casts obj into a string. obj must already be a string for this to succeed.
• obj.ToString() gets a string representation of obj by calling the ToString() method. Which is obj itself when obj is a string. This (should) never throw(s) an exception (unless obj happens to be null, obviously).

So in your specific case, both are equivalent.

Note that string is a reference type (as opposed to a value type). As such, it inherits from object and no boxing ever occurs.