AntiForgery implementation in Asp.net formats

Question

I am developing httphandler to handle some requests in Web Forms (NOT in MVC).
How can I implement a Cross Cross Site script (e.g. antiforgery in MVC)?
I want to know mre about the anti-friction mechanism in MVC.

Answer 1

If you can access the page, you can use the ViewStateUserKey property of the page. Here is an example of how to do this from inside the page, but you get the idea:

protected void Page_Init(object sender, EventArgs e)
{
    // Validate whether ViewState contains the MAC fingerprint
    // Without a fingerprint, it impossible to prevent CSRF.
    if (!this.Page.EnableViewStateMac)
    {
        throw new InvalidOperationException(
            "The page does NOT have the MAC enabled and the view" +
            "state is therefore vulnerable to tampering.");
    }

    this.ViewStateUserKey = this.Session.SessionID;
}

ViewStateUserKey , . .