objective-c HTTP POST以表单形式发送请求

// 创建URL对象
NSURL *url = [NSURL URLWithString:@"http://example.com/api"];

// 创建请求对象
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
request.HTTPMethod = @"POST";

// 设置请求体数据
NSString *postData = @"key1=value1&key2=value2";
request.HTTPBody = [postData dataUsingEncoding:NSUTF8StringEncoding];

// 创建NSURLSession对象
NSURLSession *session = [NSURLSession sharedSession];

// 创建任务
NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    if (error) {
        NSLog(@"请求失败：%@", error);
    } else {
        // 处理响应数据
        NSString *result = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
        NSLog(@"请求成功：%@", result);
    }
}];

// 启动任务
[task resume];