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iosobjective-casihttprequest

iPhone ASIHTTP - Distinguishing between API calls?


I currently have a view controller that implements ASIHTTP for handling API calls.

My view controller fires two separate calls. I need to be able to distinguish between the two calls in the -requestFinished(ASIHTTPRequest*) request method, so I can parse each one accordingly...

Is there any of doing this?


Solution

  • Use the userInfo field! That's what it's for!

    An ASIHTTPRequest (or an ASIFormDataRequest) object has a property called .userInfo that can take an NSDictionary with anything in it you want. So I pretty much always go:

    - (void) viewDidLoad { // or wherever
        ASIHTTPRequest *req = [ASIHTTPRequest requestWithUrl:theUrl];
        req.delegate = self;
        req.userInfo = [NSDictionary dictionaryWithObject:@"initialRequest" forKey:@"type"];
        [req startAsynchronous];
    }
    
    - (void)requestFinished:(ASIHTTPRequest *)request
    {
        if ([[request.userInfo valueForKey:@"type"] isEqualToString:@"initialRequest"]) {
            // I know it's my "initialRequest" .req and not some other one!
            // In here I might parse my JSON that the server replied with, 
            // assemble image URLs, and request them, with a userInfo
            // field containing a dictionary with @"image" for the @"type", for instance.
        }
    }
    

    Set a different value for the object at key @"type" in each different ASIHTTPRequest you do in this view controller, and you can now distinguish between them in -requestFinished: and handle each of them appropriately.

    If you're really fancy, you can carry along any other data that would be useful when the request finishes. For instance, if you're lazy-loading images, you can pass yourself a handle to the UIImageView that you want to populate, and then do that in -requestFinished after you've loaded the image data!