What's the main difference between int.Parse() and Convert.ToInt32

c#

Solution

If you've got a string, and you expect it to always be an integer (say, if some web service is handing you an integer in string format), you'd use `Int32.Parse()`.

If you're collecting input from a user, you'd generally use `Int32.TryParse()`, since it allows you more fine-grained control over the situation when the user enters invalid input.

`Convert.ToInt32()` takes an object as its argument. (See Chris S's answer for how it works)

`Convert.ToInt32()` also does not throw `ArgumentNullException` when its argument is null the way `Int32.Parse()` does. That also means that `Convert.ToInt32()` is probably a wee bit slower than `Int32.Parse()`, though in practice, unless you're doing a very large number of iterations in a loop, you'll never notice it.

Problem

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