安全:GET请求(参数直接在网址中)是不安全的;POST请求(参数作为请求体单独提交)安全.

/**

/**

同步连接和异步连接的区别:

同步连接:网络请求任务交由主线程完成,当主线程请求数据时,所有的用户交互都无法处理,影响用户体验.

异步连接:网络请求任务交由子线程去完成,当子线程请求数据时,主线程依然可以处理用户交互.用户体验好.

GET:

//同步请求

- (IBAction)handleSychronize:(id)sender {

//网址字符串.

NSString *urlSrtr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx?date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";

//网址字符串中若含汉字,特殊符号等,需要进行编码转化.

//ios9之前采用的编码转换方法

// [urlSrtr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

urlSrtr = [urlSrtr stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];

//1.创建NSURL网址对象

NSURL *url = [NSURL URLWithString:urlSrtr];

//2.创建请求对象

NSURLRequest *request = [NSURLRequest requestWithURL:url];

//3.连接服务器

NSURLResponse *respondse = nil;//服务器的响应对象.

NSError *error = nil;//存储链接失败的错误信息.

/**

* 同步请求:相当于把耗时的网络请求放到同一个线程(每一个程序至少有一个线程,平时写的代码都是主线程下执行的)中处理,当数据过大时,会产生界面卡顿.

NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&respondse error:&error];

//data就是我们通过网址从服务器请求到的数据.

}

//异步请求

- (IBAction)handleAsychronize:(id)sender {

//网址字符串

NSString *urlStr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx?date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";

//创建NSURL网址对象

NSURL *url = [NSURL URLWithString:urlStr];

//创建请求

NSURLRequest *request = [NSURLRequest requestWithURL:url];

//连接服务器

//参数2:[NSOperationQueue mainQueue] 获取主线程队列. 所给的线程决定block内部代码执行是在哪个线程下(UI界面上的刷新,用户交互,必须放在主线程执行.若在子线程中执行,可能会出现未知问题);

//异步请求的第一种方式: block形式.

[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _Nullable connectionError) {

//请求完成后才会回调, 返回对应的数据Data.

//response 服务器响应对象

//data 服务器返回的数据

//connectionError 连接的错误信息

//解析数据

NSLog(@"%@",data);

}];

//异步请求第二种方式:delegate形式

[NSURLConnection connectionWithRequest:request delegate:self];

}

#pragma mark - NSURLConnectionDataDelegate -

//收到服务器响应的时候

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{

//该方法是在建立连接过程中触发的,只会执行一次.

//再次创建NSMutableData对象用于拼接返回的数据

self.mutData = [NSMutableData data];

//response服务器响应对象

NSLog(@"%lld",response.expectedContentLength);

}

//接收到数据时

-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{

[self.mutData appendData:data];

}

//数据传输结束时

-(void)connectionDidFinishLoading:(NSURLConnection *)connection{

//解析数据

NSLog(@"%@",self.mutData);

}

//连接失败时

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error{

NSLog(@"%@",error);

}

POST:

//同步请求

- (IBAction)handleSychrnize:(id)sender {

//1.网址字符串

NSString *urlStr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx";

//2.若存在汉字或特殊符号需编码转化

//3.创建网址对象

NSURL *url = [NSURL URLWithString:urlStr];

//4.创建请求(可变请求对象)

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

//5.创建参数字符串

NSString *parmStr =@"date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";

//6.参数字符串转为NSData

NSData *body = [parmStr dataUsingEncoding:NSUTF8StringEncoding];

//7.设置请求体

[request setHTTPBody:body];

//8.设置请求方式:(默认请求方式是GET);

[request setHTTPMethod:@"POST"];

//requestHeader

NSDictionary *headers = [NSDictionary dictionaryWithObject:@"Bearer YWMtP_8IisA-EeK-a5cNq4Jt3QAAAT7fI10IbPuKdRxUTjA9CNiZMnQIgk0LEUE${token}" forKey:@"Authorization"];

[request setAllHTTPHeaderFields:headers];

//连接服务器,发送请求

NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];

NSLog(@"%@",data);

}

//异步请求

- (IBAction)handleAsychrnize:(id)sender {

//1.创建网址字符串

NSString *urlStr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx";

//2.创建网址对象

NSURL *url = [NSURL URLWithString:urlStr];

//3.创建请求对象

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

//4.设置请求体

//参数字符串

NSString *parmStr =@"date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";

NSData *body =[parmStr dataUsingEncoding:NSUTF8StringEncoding];

[request setHTTPBody:body];

//5.设置请求方式

[request setHTTPMethod:@"POST"];

//异步连接

[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue]completionHandler:^(NSURLResponse * _Nullable response, NSData * _Nullable data, NSError * _NullableconnectionError) {

NSLog(@"%@",data);

}];

}

session:

// SessionViewController.m

// UISenior-DataRequest

// Created by Eric on 16/4/11.

#import "SessionViewController.h"

@interface SessionViewController ()<NSURLSessionDataDelegate>

{

long long allBytes;//存储数据总长度;

}

@property(nonatomic,strong)NSMutableData *mData;

@end

@implementation SessionViewController

/**

NSURLConnection在ios9.0之后被弃用;

替代使用NSURLSession

主要提供三种功能:1.数据请求:NSURLSessionDataTask

2.下载 :NSURLSessionDownloadTask

3.上传 : NSURLSessionUploadTask

- (void)viewDidLoad {

[super viewDidLoad];

// Do any additional setup after loading the view.

//获取数据

// [self loadDataFromServer];

//GET请求

// [self getData];

//POST请求

// [self postAction];

//获取数据

// [self configureSession];

//获取数据使用delegate形式

[self delegateAction];

}

//使用session代理的方式请求数据

-(void)delegateAction{

//1.URL

NSURLRequest *request = [NSURLRequest requestWithURL:[NSURLURLWithString:@"http://img.zcool.cn/community/0332de1559f800a32f875370ac09559.jpg"]];

//使用代理形式请求数据:不能使用全局的对话对象

NSURLSessionConfiguration *configure = [NSURLSessionConfiguration defaultSessionConfiguration];

//创建session 创建的同时设置代理对象.

NSURLSession *session = [NSURLSession sessionWithConfiguration:configure delegate:self delegateQueue:[NSOperationQueue mainQueue]];

//发起任务

NSURLSessionDataTask *dataTask = [session dataTaskWithRequest:request];

//开启任务.

[dataTask resume];

}

#pragma mark -NSURLSessionDelegate -

//服务器收到响应时

-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler{

//允许响应继续接受数据 (如果不写执行到此就结束)

completionHandler(NSURLSessionResponseAllow);

//创建mData

self.mData = [NSMutableData data];

allBytes = response.expectedContentLength;

}

//接收数据时

-(void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData*)data{

//每次返回一部分数据需要拼接

[self.mData appendData:data];

//获取当前获取数据的百分比

double scale = self.mData.length*1.0 /allBytes;

self.scaleLable.text = [NSString stringWithFormat:@"%.2f%%",scale*100];

self.image.image = [UIImage imageWithData:self.mData];

// NSLog(@"%lf",scale);

}

//接收数据完成时

-(void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError*)error{

if (!error) {

NSLog(@"%@",self.mData);

}

//使用自己创建的Session发起任务.

//一般项目中,建议程序中少创建session,减少底层建立连接的过程.

- (void)configureSession{

NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx?date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213"]];

//创建对话配置对象(对会话进行设置)

/**

* 支持三种类型:default默认的;

临时会话

后台

NSURLSessionConfiguration *configure = [NSURLSessionConfiguration defaultSessionConfiguration];

NSURLSession *session = [NSURLSession sessionWithConfiguration:configure];

//使用自己创建的会话创建任务.

NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData * _Nullabledata, NSURLResponse * _Nullable response, NSError * _Nullable error) {

NSLog(@"%@",data);

}];

[task resume];

}

//POST请求

-(void)postAction{

NSURL *url = [NSURL URLWithString:@"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx"];

//创建请求

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

//设置请求方式

[request setHTTPMethod:@"POST"];

//设置请求体

NSString *parmStr =@"date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";

NSData *body = [parmStr dataUsingEncoding:NSUTF8StringEncoding];

request.HTTPBody =body;

//创建会话对象

NSURLSession *session = [NSURLSession sharedSession];

NSURLSessionDataTask *dataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *_Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {

NSLog(@"%@",data);

}];

//手动开启任务.

[dataTask resume];

}

//GET请求

-(void)getData{

NSURL *url = [NSURL URLWithString:@"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx?date=20151101&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213"];

NSURLRequest *request = [NSURLRequest requestWithURL:urlcachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:-1];

//3. NSURLSession对象

NSURLSession *session = [NSURLSession sharedSession];//获取系统为我们提供的全局绘画.

//4.创建数据请求任务

NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data,NSURLResponse * _Nullable response, NSError * _Nullable error) {

NSString *str = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];

NSLog(@"%@",str);

}];

[task resume];

}

-(void)loadDataFromServer{

//网址字符串

NSString *str = @"http://img.zcool.cn/community/0332de1559f800a32f875370ac09559.jpg";

//创建NSURL对象

NSURL *url = [NSURL URLWithString:str];

//创建请求

/*参数①:网址对象

参数②:缓存策略

参数③: 超时时间给-1代表不设置超时时间.

NSURLRequest *request = [[NSURLRequest alloc]initWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];

//使用session请求数据

//创建一个NSURLSession对象(网络绘画对象)

NSURLSession *session = [NSURLSession sharedSession];

//请求数据创建 NSURLSessionDataTask

NSURLSessionDataTask *dataTask = [session dataTaskWithRequest:request completionHandler:^(NSData * _Nullabledata, NSURLResponse * _Nullable response, NSError * _Nullable error) {

//data就是从服务器获取的数据.

//response服务器响应对象

//error 连接错误信息.

// NSLog(@"%@",data);

//1.界面上的处理需要回到主线程,执行界面刷新任务

// [self performSelectorOnMainThread:@selector(refreshUI:) withObject:data waitUntilDone:YES];

//2.GCD方式回到主线程

dispatch_async(dispatch_get_main_queue() , ^{

self.image.image =[UIImage imageWithData:data];

});

}];

//手动开始执行任务

[dataTask resume];

}

//刷新界面操作

- (void)refreshUI:(NSData *)data{

self.image.image = [UIImage imageWithData:data];

}

- (void)didReceiveMemoryWarning {

[super didReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

// Get the new view controller using [segue destinationViewController].

// Pass the selected object to the new view controller.

}

@end