NSURLConnection 同步连接 && 异步连接 GCD

//同步连接的方法
+ (NSData *)sendSynchronousRequest:(NSURLRequest *)request returningResponse:(NSURLResponse **)response error:(NSError **)error;
//异步连接的方法
+ (NSData *)sendSynchronousRequest:(NSURLRequest *)request returningResponse:(NSURLResponse **)response error:(NSError **)error;

异步连接

UIButton *button = [UIButton buttonWithType:UIButtonTypeSystem];
[button setTitle:@"GET 异步" forState:UIControlStateNormal];
button.frame = CGRectMake(100, 100, 150, 50);
[button addTarget:self action:@selector(getAsyn) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:button];

UIButton *button1 = [UIButton buttonWithType:UIButtonTypeSystem];
[button1 setTitle:@"POST 异步" forState:UIControlStateNormal];
button1.frame = CGRectMake(100, 200, 150, 50);
[button1 addTarget:self action:@selector(postAsyn) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:button1];

UIButton *button2 = [UIButton buttonWithType:UIButtonTypeSystem];
[button2 setTitle:@"TEST" forState:UIControlStateNormal];
button2.frame = CGRectMake(100, 300, 150, 50);
[button2 addTarget:self action:@selector(TEST) forControlEvents:UIControlEventTouchUpInside];
[self.window addSubview:button2];

//.h文件
@property (strong, nonatomic) UIWindow *window;
@property (strong,nonatomic) AVAudioPlayer *player;//播放mp3
@property (strong,nonatomic) NSMutableData *mData; //post方法用的
@property (nonatomic) long long totalLenght;//下载内容的总长度

//接收响应者
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
NSLog(@"%@",response);

//获取数据的总长度
_totalLenght = [response expectedContentLength];
NSLog(@"%lld",_totalLenght);
_mData = [NSMutableData data];

NSLog(@"正在开启加载模式 请稍后…");
}

//开始接收数据
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
//当前数据的长度
//    NSLog(@"--------%ld",[data length]);
[_mData appendData:data];
NSLog(@"▉▉▉▉▉%.2f%%",100.0*[_mData length] / _totalLenght);
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
//接收完毕所有的数据之后才会执行的方法
NSLog(@"播放");
_player = [[AVAudioPlayer alloc] initWithData:_mData error:nil];
[_player play];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
NSLog(@"%@",error);
}

//get方法 代理
- (void)getAsyn
{
NSString *str = @"http://yinyueshiting.baidu.com/data2/music/134368947/72104070108000128.mp3?xcode=a7d5ad2a3b062e369dfe3aa462999dd4f8a8b2fa4f50b032";
NSURL *url = [NSURL URLWithString:str];
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
//1.去掉警告的
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[connection start];
//2.下面一句
//    [NSURLConnection connectionWithRequest:request delegate:nil];

//    NSURLResponse *response = nil; //因为是**类型 下同 所以下面写 &response
//    NSError *error = nil;
//    NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];  //同步连接
//    _player = [[AVAudioPlayer alloc] initWithData:data error:nil];
//    [_player play];
}
//post方法 由于上面的百度音乐网址有误 改成了这种才可以
- (void)postAsyn
{
//post是将URL 和 参数分离的一种请求方式
NSString *str = @"http://music.baidu.com/data/music/file";
NSURL *url = [NSURL URLWithString:str];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setHTTPMethod:@"POST"];
[request setHTTPBody:[@"link=http://yinyueshiting.baidu.com/data2/music/134368947/72104070108000128.mp3?xcode=a7d5ad2a3b062e369dfe3aa462999dd4f8a8b2fa4f50b032" dataUsingEncoding:NSUTF8StringEncoding]];

NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[connection start];
//    NSURLResponse *response = nil;
//    NSError *error = nil;
//    [NSURLConnection sendAsynchronousRequest:request queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
//        _player = [[AVAudioPlayer alloc] initWithData:data error:nil];
//
//        [_player play];
//    }];

}
//block的方式
- (void)TEST
{
NSString *str = @"http://yinyueshiting.baidu.com/data2/music/134368947/72104070108000128.mp3?xcode=a7d5ad2a3b062e369dfe3aa462999dd4f8a8b2fa4f50b032";
NSURL *url = [NSURL URLWithString:str];
NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10];
[NSURLConnection sendAsynchronousRequest:request queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
_player = [[AVAudioPlayer alloc] initWithData:data error:nil];

[_player play];
}];
}

#import "AppDelegate.h"

@implementation AppDelegate

- (void)dealloc
{
[super dealloc];
}

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
// Insert code here to initialize your application
[self fetchYahooData];

NSLog(@"-------------------------------------");
[self fetchYahooData2_GCD];
NSLog(@"-------------------------------------");
[self fetchYahooData3];
}
//使用异步加载，那么就不会阻塞主线程，因为异步他会开启一个子线程去加载

//不使用GCD，同步加在数据,会阻塞主线程
-(void)fetchYahooData{
NSLog(@"同步请求测试开始...");
NSString *urlString = @"http://www.yahoo.com";
NSURL *url = [NSURL URLWithString:urlString];
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
NSURLResponse *response = nil;
NSError *error = nil;
NSLog(@"马上进行同步连接请求url的数据");
NSData *data = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:&error];
if ([data length] > 0 && error == nil) {
NSLog(@"%lu 字节的数据被返回.",(unsigned long)[data length]);
}else if([data length] == 0 && error == nil){
NSLog(@"没有数据返回");
}else if (error != nil){
NSLog(@"出现错误= %@",error);
}
NSLog(@"同步方法测试完成."); //它会等待上面的下载数据完成才打印这句话

}

//使用GCD，同步加载数据.不会阻塞主线程。
-(void)fetchYahooData2_GCD{
NSLog(@"使用GCD同步请求测试开始...");
NSString *urlString = @"http://www.yahoo.com";
NSLog(@"马上进行同步连接请求url的数据...");
dispatch_queue_t dispatchQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_async(dispatchQueue, ^{
NSURL *url = [NSURL URLWithString:urlString];
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
NSURLResponse *response = nil;
NSError *error = nil;
NSData *data = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&response error:&error];
if ([data length] > 0 && error == nil) {
NSLog(@"%lu 字节的数据被返回.",(unsigned long)[data length]);
//            [data writeToFile:@"/Users/macoslion/Desktop/new/download.html" atomically:YES]; //下载下来的数据保存为xml,或者html。最好是xml

}else if ([data length] == 0 && error == nil){
NSLog(@"没有数据返回.");
}else if (error != nil){
NSLog(@"请求出错 = %@",error);
}
});
NSLog(@"GCD测试完成."); //它会直接打印，不会等到上面下载数据完成才打印

}

//使用异步，它也不会阻塞主线程
-(void)fetchYahooData3
{
NSLog(@"异步请求测试开始..");
NSString *urlString = @"http://www.yahoo.com";
NSURL *url = [NSURL URLWithString:urlString];
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];

NSLog(@"马上进行异步连接请求url的数据...");

[NSURLConnection sendAsynchronousRequest:urlRequest queue:[NSOperationQueue currentQueue] completionHandler:^(NSURLResponse *reponse, NSData *data, NSError *error) {
if ([data length] > 0 && error == nil) {
NSLog(@"%lu 字节的数据被返回.",(unsigned long)[data length]);
}else if([data length] == 0 && error == nil){
NSLog(@"没有数据返回");
}else if (error != nil){
NSLog(@"请求出错 = %@",error);
}
}];

NSLog(@"异步方法测试完成"); //这句话不会等到上面打印完了而打印

}
@end