OC -网络请求 - NSURLConnection - POST

 #import "ViewController.h"

 @interface ViewController ()

 @end

 @implementation ViewController
 -(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
 {
     [self post];
 }

 -(void)post
 {
     //1.确定请求路径
     NSURL *url = [NSURL URLWithString:@"http://120.25.226.186:32812/login"];

     //2.创建可变请求对象
     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

     //3.修改请求方法,POST必须大写
     request.HTTPMethod = @"POST";

     //设置属性,请求超时
     request.timeoutInterval = ;

     //设置请求头User-Agent
     //注意:key一定要一致(用于传递数据给后台)
     [request setValue:@"ios 10.1" forHTTPHeaderField:@"User-Agent"];

     //4.设置请求体信息,字符串--->NSData
     request.HTTPBody = [@"username=520it&pwd=123&type=JSON" dataUsingEncoding:NSUTF8StringEncoding];

     //5.发送请求
     [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {

         //6.解析数据,NSData --->NSString
         NSLog(@"%@",[[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding]);
     }];
 }

 @end