iOS中GET 和 POST 数据请求
iOS中GET 和 POST 网络数据请求
同步请求和异步请求的差别：
1.同步请求，有主线程完成网路请求任务，在数据没有请求之前，用户的所有的交互事件应用都无法处理，会造成一种卡顿现象，影响用户体验
2.异步同步，系统默认开辟子线程完成网络请求任务，主线程依然会处理用户的交互事件，此时不会出现卡顿，一旦开辟子线程就会消耗资源(内存)，此时就是拿空间换时间
先分析下整体思路：
1.下面准备一个公用的model数据数据模型：
Business.h
#import
@interface Business : NSObject
@property(nonatomic,copy)NSString *name;//商户名
@property(nonatomic,copy)NSString *address;//商户地址
@property(nonatomic,copy)NSString *telephone;//电话号码
@property(nonatomic,copy)NSString *title;
@property(nonatomic,copy)NSString *summary;
@end
#import "Business.h"
@implementation Business
- (void)dealloc{
self.name = nil;
self.telephone = nil;
self.address = nil;
self.title = nil;
self.summary = nil;
[super dealloc];
}
//防止Crash
- (void)setValue:(id)value forUndefinedKey:(NSString *)key{
}
@end 2.下面准备两个自定义的cell用于两种数据请求的自定义cell：
第一个自定义cell：
BusinessCell.h
#import
@class Business;
@interface BusinessCell : UITableViewCell
@property (retain, nonatomic) IBOutlet UILabel *nameLabel;
@property (retain, nonatomic) IBOutlet UILabel *adressLabel;
@property (retain, nonatomic) IBOutlet UILabel *telephoneLabel;
//写一个接口给cell上的子控件赋值
- (void)assignValueByBusiness : (Business *)business;
@end BusinessCell.m
#import "BusinessCell.h"
#import "Business.h"
@implementation BusinessCell
- (void)awakeFromNib {
// Initialization code
}
//写一个接口给cell上的子控件赋值
- (void)assignValueByBusiness : (Business *)business{
self.nameLabel.text = business.name;
self.telephoneLabel.text = business.telephone;
self.adressLabel.text = business.address;
}
- (void)dealloc {
[_nameLabel release];
[_adressLabel release];
[_telephoneLabel release];
[super dealloc];
}@end
CustomCell.h
#import
@class Business;
@interface CustomCell : UITableViewCell
@property (retain, nonatomic) IBOutlet UILabel *titleLabel;
@property (retain, nonatomic) IBOutlet UILabel *summaryLabel;
//写一个方法给cell上的控件赋值
- (void)setValueByName : (Business *)business;
@end
#import "CustomCell.h"
#import "Business.h"
@implementation CustomCell
- (void)dealloc {
[_titleLabel release];
[_summaryLabel release];
[super dealloc];
}
//写一个方法给cell上的控件赋值
- (void)setValueByName : (Business *)business{
self.titleLabel.text = business.title;
self.summaryLabel.text = business.summary;
}@end——————————————开始介绍数据请求：————————————————
GET数据请求(同步请求)：#import "GETViewController.h"
#import "Business.h"
#import "CustomCell.h"
#import "BusinessCell.h"
@interface GETViewController ()
@property(nonatomic,retain)NSMutableArray *dataSource;
@property(nonatomic,retain)NSMutableData *data;//拼接多次请求下来的数据
@end
@implementation GETViewController
- (void)dealloc{
self.dataSource = nil;
self.data = nil;
[super dealloc];
}
//懒加载
- (NSMutableArray *)dataSource{
if (_dataSource == nil) {
self.dataSource = [NSMutableArray arrayWithCapacity:0];
}
return [[_dataSource retain]autorelease];
}
//同步get请求
- (IBAction)handleGetSyncRequst:(UIBarButtonItem *)sender {
//清空数组
[self.dataSource removeAllObjects];
//1.准备网址字符串
NSString *urlStr = @"http://api.map.baidu.com/place/v2/search?query=大保健®ion=上海&output=json&ak=6E823f587c95f0148c19993539b99295";
//2.查看网址字符串中是否含有中文,有中文的话要对urlStr进行转码
NSString *changeUrlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
//3.创建NSURL对象,不能能够存储本地的文件地址，也能存储网络地址
NSURL *url = [NSURL URLWithString:changeUrlStr];
//4.创建网络请求对象(NSURLRequest )
// NSURLRequest 默认请求方式就是GET请求
// NSMutableURLRequest 可以设置网络的请求方式
NSURLRequest *request = [NSURLRequest requestWithURL:url];
//5.建立同步链接
//5.1 创建服务器响应对象
NSURLResponse *response = nil;
//5.2 创建请求失败错误信息对象
//以上两个参数都是方法的内部对其赋值
NSError *error = nil;
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
// NSLog(@"%@",data); 验证！
//调用解析方法
[self parserData:data];
}
//封装一个解析的方法
- (void)parserData : (NSData *)data{
//解析：
NSMutableDictionary *dataDic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
// NSLog(@"%@",dataDic); 验证！
//取出results key值对应的数组
NSArray *array = dataDic[@"results"];
//遍历数组的字典，并使用给Business对象赋值
for (NSDictionary *dic in array) {
//创建数据模型对象
Business *bus = [[Business alloc]init];
//使用kvc给bus赋值
[bus setValuesForKeysWithDictionary:dic];
//添加到存储所有商户信息的数组
[self.dataSource addObject:bus];
//释放
[bus release];
// NSLog(@"%@",self.dataSource); 验证！
}
//刷新ui界面
[self.tableView reloadData];
}//异步get请求
- (IBAction)handleGetAsyncRequst:(UIBarButtonItem *)sender {
//清空数组
self.dataSource = nil;
//1.创建网址字符串
NSString *urlStr = @"http://api.map.baidu.com/place/v2/search?query=大保健®ion=上海&output=json&ak=6E823f587c95f0148c19993539b99295";
//2.判断是否含有中文
NSString *change = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
//3.创建NSURL对象
NSURL *url = [NSURL URLWithString:change];
//4.创建网络请求
NSURLRequest *requst = [NSURLRequest requestWithURL:url];
//5.创建异步网络连接
// NSOperationQueue 队列类
// [NSOperationQueue mainQueue] 获取主队类
/*
//让当前的self 对象处于引用状态
__block typeof(self) weakSelf = self;
[NSURLConnection sendAsynchronousRequest:requst queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
//data 就是请求下来的数据
//response 就是响应对象
//connectionError 就是存放连接时报错信息的对象
//调用解析方法
[weakSelf parserData:data];
}];
*/
//代理完成异步解析
[NSURLConnection connectionWithRequest:requst delegate:self];
}
代理完成异步解析：
#pragma mark NSURLConnection 代理方法
//当接收到服务器响应的时候触发
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response{
//一旦接收到服务器的响应,就创建拼接的data对象
self.data = [NSMutableData data];
}
//当接收到服务器数据的时候触发
//此方法有可能触发多次,原因：1.网络环境比较差时 2.请求的数据量比较大的时候,此时服务器会分多次把数据传输过来
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{
//拼接服务器传输的数据
[self.data appendData:data];
}
//当接收到服务器传输数据结束的时候触发
- (void)connectionDidFinishLoading:(NSURLConnection *)connection{
//此时数据已经接收完毕，可以解析了
[self parserData:self.data];
}
- (void)viewDidLoad {
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return self.dataSource.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
BusinessCell *cell = [tableView dequeueReusableCellWithIdentifier:@"getcell" forIndexPath:indexPath];
//调用cell的控件的赋值方法
[cell assignValueByBusiness:self.dataSource[indexPath.row]];
return cell;
}
查看效果：
GET同步和异步数据请求效果：
—————————— 
————————————————POST数据请求——————————————————————
定义相关属性：
#import "POSTViewController.h"
#import "Business.h"
#import "CustomCell.h"
@interface POSTViewController ()
@property(nonatomic,retain)NSMutableArray *dataSource;
@end
@implementation POSTViewController
- (void)dealloc{
self.dataSource = nil;
[super dealloc];
}
- (NSMutableArray *)dataSource{
if (_dataSource == nil) {
self.dataSource = [NSMutableArray arrayWithCapacity:0];
}
return [[_dataSource retain]autorelease];
}
//Post同步
//http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx/
//date=20131129&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213
- (IBAction)handlePostSyncRequst:(UIBarButtonItem *)sender {
[self.dataSource removeAllObjects];
//1.准备网址字符串
NSString *urlStr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx/";
//2.创建NSURL对象
NSURL *url = [NSURL URLWithString:urlStr];
//3.创建网络请求对象
NSMutableURLRequest *requst = [NSMutableURLRequest requestWithURL:url];
//3.1配置请求方式
requst.HTTPMethod = @"POST";
//4.创建参数字符串
NSString *bodyString = @"date=20131129&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";
//将字符串转换为NSDate独享
NSData *data = [bodyString dataUsingEncoding:NSUTF8StringEncoding];
//配置网络请求的方式
requst.HTTPBody = data;
//5.创建网络链接
NSURLResponse *response = nil;
NSError *error = nil;
NSData *data1 = [NSURLConnection sendSynchronousRequest:requst returningResponse:&response error:&error];
// NSLog(@"%@",data1);
[self parserData: data1];
}
//post异步
- (IBAction)handlePostAsyncRequest:(UIBarButtonItem *)sender {
[self.dataSource removeAllObjects];
//1.创建网址字符串
NSString *urlStr = @"http://ipad-bjwb.bjd.com.cn/DigitalPublication/publish/Handler/APINewsList.ashx/";
//2.创建NSURL对象
NSURL *url = [NSURL URLWithString:urlStr];
//3.创建网络请求对象
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
//3.1创建请求方式
request.HTTPMethod = @"POST";
//4.创建参数对象
NSString *bodyString = @"date=20131129&startRecord=1&len=5&udid=1234567890&terminalType=Iphone&cid=213";
NSData *data = [bodyString dataUsingEncoding:NSUTF8StringEncoding];
//设置请求对象的body
request.HTTPBody = data;
//5.创建网络链接
__block typeof(self) weakself = self;
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
// NSLog(@"%@",data);
[weakself parserData:data];
}];
}
封装一个解析的方法
- (void)parserData : (NSData *)data{
//解析：
NSMutableDictionary *dataDic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
// NSLog(@"%@",dataDic); //验证！
//取出results key值对应的数组
NSArray *array = dataDic[@"news"];
// NSLog(@"%@",array);
//遍历数组的字典，并使用给Business对象赋值
for (NSDictionary *dic in array) {
//创建数据模型对象
Business *bus = [[Business alloc]init];
//使用kvc给bus赋值
[bus setValuesForKeysWithDictionary:dic];
// NSLog(@"%@",bus);
//添加到存储所有商户信息的数组
[self.dataSource addObject:bus];
//释放
[bus release];
// NSLog(@"%@",self.dataSource); //验证！
}
//刷新ui界面
[self.tableView reloadData];
}- (void)viewDidLoad {
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
// Return the number of rows in the section.
return self.dataSource.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:@"post" forIndexPath:indexPath];
[cell setValueByName:self.dataSource[indexPath.row]];
return cell;
}POST两种数据请求完成！
查看两种效果效果：
————————————
————————————————————————————————————————————
——————————————介绍同步卡顿现象——————————————————————
BigImageViewController.m
@interface BigImageViewController ()
@property (retain, nonatomic) IBOutlet UIImageView *bigImageView;
@end
@implementation BigImageViewController
- (IBAction)handleKaDun:(UIButton *)sender {
//1.准备网址字符串
NSString *urlStr = @"http://f1.topit.me/1/d2/8c/11663656284128cd21o.jpg";
//2.初始化NSURL对象
NSURL *url = [NSURL URLWithString:urlStr];
//3.创建请求对象
NSURLRequest *request = [NSURLRequest requestWithURL:url];
//4.建立网络连接
//4.1创建响应度向
NSURLResponse *response = nil;
NSError *errror = nil;
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&errror];
//音乐数据，视频数据，图片数据不需要解析直接可以使用
self.bigImageView.image = [UIImage imageWithData:data];
}
————————————————————————————————————————————