How to send POST and GET request?

Aleksander Azizi picture Aleksander Azizi · Oct 6, 2011 · Viewed 94.1k times · Source

I want to send my JSON to a URL (POST and GET).

NSMutableDictionary *JSONDict = [[NSMutableDictionary alloc] init];
[JSONDict setValue:"myValue" forKey:"myKey"];

NSData *JSONData = [NSJSONSerialization dataWithJSONObject:self options:kNilOptions error:nil];

My current request code isn't working.

NSMutableURLRequest *requestData = [[NSMutableURLRequest alloc] init];

[requestData setURL:[NSURL URLWithString:@"http://fake.url/"];];

[requestData setHTTPMethod:@"POST"];
[requestData setValue:postLength forHTTPHeaderField:@"Content-Length"];
[requestData setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[requestData setValue:@"application/json" forHTTPHeaderField:@"Accept"];
[requestData setHTTPBody:postData];

Using ASIHTTPRequest is not a liable answer.

Answer

Aleksander Azizi picture Aleksander Azizi · Jul 17, 2012

Sending POST and GET requests in iOS is quite easy; and there's no need for an additional framework.


POST Request:

We begin by creating our POST's body (ergo. what we'd like to send) as an NSString, and converting it to NSData.

NSString *post = [NSString stringWithFormat:@"test=Message&this=isNotReal"];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];

Next up, we read the postData's length, so we can pass it along in the request.

NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];

Now that we have what we'd like to post, we can create an NSMutableURLRequest, and include our postData.

NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:@"http://YourURL.com/FakeURL"]];
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setHTTPBody:postData];

let post = "test=Message&this=isNotReal"
let postData = post.data(using: String.Encoding.ascii, allowLossyConversion: true)

let postLength = String(postData!.count)

var request = URLRequest(url: URL(string: "http://YourURL.com/FakeURL/PARAMETERS")!)
request.httpMethod = "POST"
request.addValue(postLength, forHTTPHeaderField: "Content-Length")
request.httpBody = postData;

And finally, we can send our request, and read the reply by creating a new NSURLSession:

NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
[[session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    NSString *requestReply = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];
    NSLog(@"Request reply: %@", requestReply);
}] resume];

let session = URLSession(configuration: .default)
session.dataTask(with: request) {data, response, error in
    let requestReply = NSString(data: data!, encoding: String.Encoding.ascii.rawValue)
    print("Request reply: \(requestReply!)")
}.resume()

GET Request:

With the GET request it's basically the same thing, only without the HTTPBody and Content-Length.

NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
[request setURL:[NSURL URLWithString:@"http://YourURL.com/FakeURL/PARAMETERS"]];
[request setHTTPMethod:@"GET"];

NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
[[session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    NSString *requestReply = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];
    NSLog(@"Request reply: %@", requestReply);
}] resume];

var request = URLRequest(url: URL(string: "http://YourURL.com/FakeURL/PARAMETERS")!)
request.httpMethod = "GET"

let session = URLSession(configuration: .default)
session.dataTask(with: request) {data, response, error in
    let requestReply = NSString(data: data!, encoding: String.Encoding.ascii.rawValue)
    print("Request reply: \(requestReply!)")
}.resume()

On a side note, you can add Content-Type (and other data) by adding the following to our NSMutableURLRequest. This might be required by the server when requesting, e.g, a .

[request setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[request setValue:@"application/json" forHTTPHeaderField:@"Accept"];

Response code can also be read using [(NSHTTPURLResponse*)response statusCode].

request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")

Update: sendSynchronousRequest is deprecated from and (10.11) and out.

NSURLResponse *requestResponse; NSData *requestHandler = [NSURLConnection sendSynchronousRequest:request returningResponse:&requestResponse error:nil]; NSString *requestReply = [[NSString alloc] initWithBytes:[requestHandler bytes] length:[requestHandler length] encoding:NSASCIIStringEncoding]; NSLog(@"requestReply: %@", requestReply);