Question

所以我有一些像这样的代码：

@interface RequestHandler()

@property (nonatomic) NSInteger statusCode;

@end

@implementation RequestHandler

- (bool)sendRequest:(NSString *)surveyorId withData:(NSData *)requestData
{
    [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:true];

    if (self.statusCode == 200)
    {
        return YES;
    }

    return NO;
}

显然，例程将在请求完成之前继续进入if-else语句。因此，在检查之前，self.statusCode未在委托didReceiveResponse中正确设置。这样做的最佳方式是什么？

我只想添加另一个bool属性，该属性将在connectionDidFinishLoading中设置，然后循环直到设置此属性。完成后，它会检查self.statusCode。但是我在想这会阻塞线程吗？它与sendSynchronousRequest权利没有什么不同？如果不将它放入后台线程，有没有办法做到这一点？

Answer 1

而不是您的sendRequest:withData:方法返回指示成功/失败的BOOL，您的RequestHandler最好有一个委托。然后，它可以让其代理知道异步请求完成时的成功/失败/其他任何事情，而不是尝试从sendRequest:withData:方法返回此信息（正如您已经发现的那样，＃39;工作得很好。）

所以，您可以定义委托协议这样的东西（仅作为示例 - 您可能希望在这些中包含更多信息）：

@protocol RequestHandlerDelegate <NSObject>

- (void)requestHandlerSuccessfullyCompletedRequest:(RequestHandler *)sender;
- (void)requestHandlerFailedToCompletedRequest:(RequestHandler *)sender;

@end

然后，为RequestHandler提供符合此协议的委托属性：

@property (nonatomic, weak) id<RequestHandlerDelegate> delegate;

（确保将某些内容设置为代理人！）

然后，当您的异步请求完成时，您可以向您的代理发送相应的消息，例如：

[self.delegate requestHandlerSuccessfullyCompletedRequest:self];

您需要在NSURLConnection中实施RequestHandler委托方法（来自您的代码，我假设您已经完成了此操作），或者，如果您的目标是iOS 7 +，您可以改为查看NSURLSession。

Answer 2

您必须实现2个委托方法：

状态代码：- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
收到的数据：- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data

示例用法：

<强>声明

@interface RequestHandler : NSObject <NSURLConnectionDelegate>
{
    NSMutableData *receivedData;
}

请求

- (void)sendRequest:(NSString *)surveyorId withData:(NSData *)requestData { NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init]; // Apply params in http body if (requestData) { [request setHTTPBody:requestData]; } [request setURL:url]; NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self]; [connection start]; }

<强>代表

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response { NSHTTPURLResponse *responseCode = (NSHTTPURLResponse *)response; if ([self.delegate respondsToSelector:@selector(didReceiveResponseCode:)]) { [self.delegate didReceiveResponseCode:responseCode]; } } - (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data { receivedData = [[NSMutableData alloc] initWithData:data]; if ([self.delegate respondsToSelector:@selector(connectionSucceedWithData:)]) { [self.delegate connectionSucceedWithData:receivedData]; } }

Answer 3

您可以在代码中使用NSURLConnection sendAsynchronousRequest块，而不是将NSURLConnection与委托方法一起使用。在该示例中，您可以检查连接错误并比较状态代码。

NSURL *URL = [NSURL URLWithString:@"http://yourURLHere.com"];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:URL];

[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *rspreportStatus, NSData *datareportStatus, NSError *e)
{

    NSHTTPURLResponse* httpResponse = (NSHTTPURLResponse*)rspreportStatus;
    int code = [httpResponse statusCode];

    if (e == nil && code == 200)
    {
        // SUCCESS
    } else {
        // NOT SUCCESS
    }
}];

Answer 4

您也可以通过记录此returnString来检查。

        NSData *returnData = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
        NSString *returnString = [[NSString alloc] initWithData:returnData encoding:NSUTF8StringEncoding];
        NSArray *arrpicResult = [returnString JSONValue];

NSURLConnection sendAsynchronousRequest：如何检查完成状态代码？

4 个答案: