ASP.NET覆盖Web方法

Question

I have several WebMethods in a C# ASP.NET web app. I'd like to change the behavior of all of them to validate each request. Imagine the code below:

[WebMethod]
public static void DoSomething() 
{
    if (ValidateRequest())
    {
        HttpContext.Current.Response.StatusCode = 400;
        // do some other stuff
        return;
    }
    // rest of method
}

I've noticed of course that the ValidateRequest() method call is common to a large portion of my WebMethods. Is there anyway I can wire this up so that all WebMethods automatically have this same behavior? Could I add a second attribute to the method to accomplish this?

Answer 1

Add the validate request in the Begin Request of your Global.asax file.

Now, you need some sort of code to check if the request should be validated.

I'm unsure how to do this in webforms... But, what I'd do is:

use the RequestPath property (and get the method and class name if they match your service URL)

HttpContext.Current.Request.Path;

Then I would create a method attribute and perhaps use reflection to see if the request should be validated. (see link below)

http://msdn.microsoft.com/en-us/library/z919e8tw.aspx

This way from this point on you just need to tag your method with your "[Validate]" attribute and it all should just work.

 public class Global : HttpApplication
    {
        protected void Application_BeginRequest(object sender, EventArgs e)
        {
          if(ShouldValidate() && !IsValidRequest()){
              //add your custom error status here perhaps
              Response.StatusCode = 400
              Response.StatusDescription = "Something Bad happened"
              HttpContext.Current.Response.End()
          }
        }