iOS 7 Programming Cookbook

11.7. Sending HTTP DELETE Requests with NSURLConnection

Problem

You want to call a web service using the HTTP DELETE method to delete a resource from a URL, and perhaps pass parameters, as part of the HTTP body or in the query string, to the web service.

Solution

Just as with the GET and POST methods, you can use the DELETE method using NSURLConnection. You must explicitly set your URL’s method to DELETE.

Discussion

Let’s write a simple app that can create an asynchronous connection and send a few parameters as a query string and a few parameters in the HTTP body to the aforementioned URL, using the DELETE HTTP method:

- (BOOL)            application:(UIApplication *)application
  didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{

    NSString *urlAsString = <# Place the URL of the web server here #>;
    urlAsString = [urlAsString stringByAppendingString:@"?param1=First"];
    urlAsString = [urlAsString stringByAppendingString:@"&param2=Second"];

    NSURL *url = [NSURL URLWithString:urlAsString];

    NSMutableURLRequest *urlRequest =
        [NSMutableURLRequest requestWithURL:url];

    [urlRequest setTimeoutInterval:30.0f];
    [urlRequest setHTTPMethod:@"DELETE"];

    NSString *body = @"bodyParam1=BodyValue1&bodyParam2=BodyValue2";
    [urlRequest setHTTPBody:[body dataUsingEncoding:NSUTF8StringEncoding]];

    NSOperationQueue *queue = [[NSOperationQueue alloc] init];

    [NSURLConnection
     sendAsynchronousRequest:urlRequest
     queue:queue
     completionHandler:^(NSURLResponse *response,
                         NSData *data,
                         NSError *error) {

         if ([data length] >0  && ...