Difference between Object type casting (as / (int)) in C# [duplicate]

Question

Possible Duplicate:
What is the difference between the following casts in c#?

While am working on C#, her am doing type casting at that point I got a doubt:-

What is the difference between Object type casting for "as vs. (int)/(string)/... soon"?

Example:

int a = (int) value;

VS.

int a = value as int;

---

string a = (string) value;

VS.

string a = value as string;

---

and soon...

Can any help explain this in detail?

Thanks in advance.

Answer 1

From msdn:

The as operator is used to perform certain types of conversions between compatible reference or nullable types.

Remarks:

The as operator is like a cast operation. However, if the conversion is not possible, as returns null instead of raising an exception. Consider the following expression:

expression as type

It is equivalent to the following expression except that expression is evaluated only one time.

expression is type ? (type)expression : (type)null

Note that the as operator only performs conversions to reference or nullable types, and boxing conversions. The as operator cannot perform other conversions, such as user-defined conversions, which should instead be performed by using cast expressions.