objective-c - 如何发送 POST 和 GET 请求？

Question

我想将我的 JSON 发送到 URL(POST 和 GET)。

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

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

---

我当前的请求代码不起作用。

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];

---

使用 ASIHTTPRequest 是不是可靠的答案。

Answer 1

在 iOS 中发送 POST 和 GET 请求非常简单；并且不需要额外的框架。

---

POST 请求:

我们首先将 POST 的 body(我们想发送的内容)创建为 NSString，然后转换它到 NSData.

objective-c

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

接下来，我们读取 postData 的 length，以便在请求中传递它。

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

现在我们有了想要发布的内容，我们可以创建一个 NSMutableURLRequest，并包含我们的 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];

swift

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;

最后，我们可以发送我们的请求，并通过创建一个新的 NSURLSession 来读取回复:

objective-c

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];

swift

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 请求:

GET 请求基本上是一样的，只是没有 HTTPBody 和Content-Length。

objective-c

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];

swift

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()

---

附带说明，您可以通过将以下内容添加到我们的 NSMutableURLRequest 来添加 Content-Type(和其他数据)。这可能是服务器在请求时需要的，例如 json .

objective-c

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

也可以使用 [(NSHTTPURLResponse*)response statusCode] 读取响应代码。

swift

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

---

更新: sendSynchronousRequest 在 ios9 中被弃用和 osx-elcapitan (10.11) 出。

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);