//分界线的标识符
    NSString *TWITTERFON_FORM_BOUNDARY = @"AaB03x";
    NSString *urlString =  @"";
    NSMutableURLRequest* request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:urlString]
                                                           cachePolicy:NSURLRequestReloadIgnoringLocalCacheData
                                                       timeoutInterval:10];
    NSString *MPboundary=[[NSString alloc]initWithFormat:@"--%@",TWITTERFON_FORM_BOUNDARY];
    NSString *endMPboundary=[[NSString alloc]initWithFormat:@"%@--",MPboundary];
    //要上传的图片
    NSDictionary  *params = [[NSDictionary alloc] init];
    UIImage *image = [UIImage imageNamed:@"0.JPG"];
    NSData *image2 = UIImageJPEGRepresentation(image, 0.5);
    NSMutableString *body=[[NSMutableString alloc]init];
    NSArray *keys = [[NSArray alloc] initWithObjects:@"desc",@"albumId",@"sid",nil];
    for(int i=0;i<[keys count];i++)
    {
        NSString *key=[keys objectAtIndex:i];
        if(![key isEqualToString:@"pic"])
        {
            [body appendFormat:@"%@\r\n",MPboundary];
            [body appendFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n",key];
            [body appendFormat:@"%@\r\n",@"119"];  
        }
    }
    
    [body appendFormat:@"%@\r\n",MPboundary];
    [body appendFormat:@"Content-Disposition: form-data; name=\"picFile\"; filename=\"picFile.png\"\r\n"];
    [body appendFormat:@"Content-Type: image/png\r\n\r\n"];
    NSString *end=[[NSString alloc]initWithFormat:@"\r\n%@",endMPboundary];
    NSMutableData *myRequestData=[NSMutableData data];
    [myRequestData appendData:[body dataUsingEncoding:NSUTF8StringEncoding]];
    [myRequestData appendData:image2];
    [myRequestData appendData:[end dataUsingEncoding:NSUTF8StringEncoding]];
    NSString *content=[[NSString alloc]initWithFormat:@"multipart/form-data; boundary=%@",TWITTERFON_FORM_BOUNDARY];
    [request setValue:content forHTTPHeaderField:@"Content-Type"];
    [request setValue:[NSString stringWithFormat:@"%d", [myRequestData length]] forHTTPHeaderField:@"Content-Length"];
    [request setHTTPBody:myRequestData];
    [request setHTTPMethod:@"POST"];  
    //建立连接，设置代理
    NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:request delegate:self];
    if(conn){
        NSLog(@"连接成功");
    }
    //提示用户上传成功  需要判断返回的json
    NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
    UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"通知"
                                                message:@"图片上传成功"
                                                delegate:self
                                                cancelButtonTitle:@"Cancel"
                                                otherButtonTitles:nil, nil];
    [alert show];
    NSLog(@"%@",returnString);