How to make a Generic Type Cast function

Possible Duplicate:
is there a generic Parse() function that will convert a string to any type using parse?

I want to make a generic function for doing some operations, like:

ConvertValue<T>(string value)

If T is int then the function will convert the value to int and return the result.

Similarly, if T is boolean, the function will convert the value to boolean and return it.

How to write this?