iOS应用中发送HTTP的get请求以及HTTP异步请求的方法

http get 请求

// 组合一个搜索字符串
    nsstring *urlstr = [nsstring stringwithformat:@"http://www.baidu.com/s?wd=%@", @"php"];
    // 字符串转化为url
    nsurl *url = [nsurl urlwithstring:urlstr];
    
//    nsmutableurlrequest *request = [[nsmutableurlrequest alloc] init];
//    [request seturl:url];
//    [request sethttpmethod:@"post"];
//    [request settimeoutinterval:60];
//    [request sethttpbody:_data];
//    [request setvalue:@"ttt" forhttpheaderfield:@"cookies"];
   
    // url转化为一个请求
    nsurlrequest *request = [nsurlrequest requestwithurl:url];
    // 状态请求
    nsurlresponse *response;
    // 链接一个请求
    nsdata *resultdata = [nsurlconnection sendsynchronousrequest:request returningresponse:&response error:nil];
    // 返回数据转为字符串
    nsdata *datastring = [[nsstring alloc] initwithdata:resultdata encoding:nsutf8stringencoding];
    nslog(@"%@", datastring);
// 解析json吧

http异步请求

- (void)viewdidload
{
    [super viewdidload];
    // do any additional setup after loading the view.
    
    _data = [[nsmutabledata alloc] init];
    
    // 组合一个搜索字符串
    nsstring *urlstr = [nsstring stringwithformat:@"http://www.baidu.com/s?wd=%@", @"php"];
    nsurl *url = [nsurl urlwithstring:urlstr];
    
    nsurlrequest *request = [nsurlrequest requestwithurl:url];
    
    //发起请求，定义代理
    [nsurlconnection connectionwithrequest:request delegate:self];
    
}
 
// 分批返回数据
- (void)connection:(nsurlconnection *) connection didreceivedata:(nsdata *)data {
    [_data appenddata:data];
    nslog(@"%@", _data);
}
 
// 数据完全返回完毕
- (void)connectiondidfinishloading:(nsurlconnection *)connection {
    nsstring *datastring =  [[nsstring alloc] initwithdata:_data encoding:nsutf8stringencoding];
    nslog(@"%@", datastring);
}