POST请求的两种方式

在ViewController中的代码如下

- (void)viewDidLoad {
    [super viewDidLoad];

    NSString *urlStr1 = @"http://localhost/cgi-bin/post1.cgi";
    NSString *urlStr2 = @"http://localhost/cgi-bin/post2.cgi";
    
//    [self sendPost1:urlStr1];
    [self sendPost2:urlStr2];
}

#pragma mark -send POST 2-
/**
    使用NSData（二进制数据）承载请求信息，多用于上传文件
 */
-(void)sendPost2:(NSString*)urlStr{
    //准备工作(规定好了的格式)
    NSString *head = @"Content-type: multipart/form-data, boundary=AaB03x

";
    //规定分隔符
    NSString *boundary = @"AaB03x";
    //头的分隔符
    NSString *headBoundary = [NSString stringWithFormat:@"--%@
",boundary];
    //尾的分隔符
    NSString *endBoundary = [NSString stringWithFormat:@"
--%@--
",boundary];
    
    //封装请求头
    NSString *contentString = @"content-disposition: form-data; name="pic"; filename="star_pressed.png"Content-Type: image/png

";
    
    //创建请求
    NSURL *url = [NSURL URLWithString:urlStr];
    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]initWithURL:url];
    
    //对请求操作
    [request setHTTPMethod:@"POST"];
    //设置上传数据的格式
    [request addValue:@"multipart/form-data" forHTTPHeaderField:@"Content-Type"];
    
    //设置body
    NSData *fileData = [NSData dataWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"star_pressed" ofType:@"png"]];
    
    //设置总的请求体
    NSMutableData *data = [NSMutableData data];
    
    //报头文 = 头 + 头分隔符 + 内容说明 + body实体 + 尾分隔符
    
    [data appendData:[head dataUsingEncoding:NSUTF8StringEncoding]];
    [data appendData:[headBoundary dataUsingEncoding:NSUTF8StringEncoding]];
    [data appendData:[contentString dataUsingEncoding:NSUTF8StringEncoding]];
    [data appendData:fileData];
    [data appendData:[endBoundary dataUsingEncoding:NSUTF8StringEncoding]];
    
    //设置请求数据的长度
    [request setValue:[NSString stringWithFormat:@"%lu",(unsigned long)data.length] forHTTPHeaderField:@"Content-Length"];
    
    [request setHTTPBody:data];
    
    //创建请求，等待返回
    _connection = [[NSURLConnection alloc]initWithRequest:request delegate:self];
}

#pragma mark -send POST 1-
/**
    GET相似，使用url承载请求信息，多用于登陆注册，填表等操作（这种方式的POST请求也能用GET请求实现，但是GET请求，发送的数据是裸露的）
 */
-(void)sendPost1:(NSString*)urlStr{
    NSURL *url = [NSURL URLWithString:urlStr];
    
    NSMutableURLRequest *request = [[NSMutableURLRequest alloc]initWithURL:url];
    
    //规定请求方式为POST请求
    [request setHTTPMethod:@"POST"];
    //要上传的数据
    NSString *postStr = @"username=jingjing&password=woxiangjingjing&message=yueme";
    //转化成二进制数据
    NSData *postData = [postStr dataUsingEncoding:NSUTF8StringEncoding];
    //设置请求体
    [request setHTTPBody:postData];
    
    //设置请求数据的长度
    [request setValue:[NSString stringWithFormat:@"%lu",(unsigned long)postData.length] forHTTPHeaderField:@"Content-Length"];
    
    //设置上传数据的格式
    [request addValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
    
    //创建请求，等待返回
    _connection = [[NSURLConnection alloc]initWithRequest:request delegate:self];
}



#pragma mark -代理方法-

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

    NSLog(@"接收到响应头");
    NSLog(@"response:%@",response);
    
    if (_data == nil) {
        _data = [[NSMutableData alloc]init];
    }
    _data.length = 0;
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data{
    [_data appendData:data];
    
    NSLog(@"收到数据。。。。：%ld",data.length);

}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection{
    NSString *str = [[NSString alloc]initWithData:_data encoding:NSUTF8StringEncoding];
    NSLog(@"接收数据完毕：
%@",str);
}

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



- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}