1. 同步發送
- (NSString *)sendRequestSync
{
// 初始化請求, 這里是變長的, 方便擴展
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
// 設置
[request setURL:[NSURL URLWithString:urlStr]];
[request setHTTPMethod:@"POST"];
[request setValue:host forHTTPHeaderField:@"Host"];
NSString *contentLength = [NSString stringWithFormat:@"%d", [content length]];
[request setValue:contentLength forHTTPHeaderField:@"Content-Length"];
[request setHTTPBody:content];
// 發送同步請求, data就是返回的數據
NSError *error = nil;
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:nilerror:&error];
if (data == nil) {
NSLog(@"send request failed: %@", error);
return nil;
}
NSString *response = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"response: %@", response);
return response;
}
2.異步發送
1) 使用delegate的方式:
- (void)sendRequestAsync
{
// 初始化請求
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
// 設置
[request setURL:[NSURL URLWithString:urlStr]];
[request setCachePolicy:NSURLRequestUseProtocolCachePolicy
]; // 設置緩存策略
[request setTimeoutInterval:5.0
]; // 設置超時
//......
receivedData
= [[NSMutableData alloc] initData: nil];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request
delegate:self];
if (connection == nil) {
// 創建失敗
return;
}
}
異步發送使用代理的方式, 需要實現以下delegate接口:
// 收到回應
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
NSLog(@"receive the response");
// 注意這里將NSURLResponse對象轉換成NSHTTPURLResponse對象才能去
NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse*)response;
if ([response respondsToSelector:@selector(allHeaderFields)]) {
NSDictionary *dictionary = [httpResponse allHeaderFields];
NSLog(@"allHeaderFields: %@",dictionary);
}
[receivedData setLength:0];
}
// 接收數據
- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
NSLog(@"get some data");
[receivedData appendData:data];
}
// 數據接收完畢
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
NSString *results = [[NSString alloc]
initWithBytes:[receivedData bytes]
length:[receivedData length]
encoding:NSUTF8StringEncoding];
NSLog(@"connectionDidFinishLoading: %@",results);
}
// 返回錯誤
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error
{
NSLog(@"Connection failed: %@", error);
}
2) iOS 5.0版本新增異步發送接口:
+ (void)sendAsynchronousRequest:(NSURLRequest *)request
queue:(NSOperationQueue*) queue
completionHandler:(void (^)(NSURLResponse*, NSData*, NSError*)) handlerNS_AVAILABLE(10_7, 5_0);