Question

我正在尝试使用下面的代码来“触发”网址。 Web服务器不返回任何数据。但NSURLConnection正在建立。

NSString *serverAddressTest = @"http://domain.com";
NSString *fullWebAddress = [NSString stringWithFormat:@"%@?CustomerName=%@&ContactNo=%@&Products=%@",serverAddressTest,customer,contactnumber,allProductsInString];

NSURL *url = [NSURL URLWithString:fullWebAddress];
NSURLRequest *theRequest=[NSURLRequest requestWithURL:url];
NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
if (theConnection) {
    NSMutableData *webData = [NSMutableData data];
    NSLog(@"%@",webData);
}
else {
    NSMutableData *webData = [NSMutableData data];
    NSLog(@"%@",webData);
}

Answer 1

当你写：

NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest
                                                               delegate:self];

您正在启动异步网址连接。

然后，您将立即测试连接是否成功，并使用 local 范围创建NSMutableData的实例。您的NSURLConnectionDelegate方法（您尚未发布）无法访问此本地范围的NSMutableData变量。

您是否确实实施了NSURLConnectionDelegate协议的方法？

Answer 2

尝试发送同步请求以本地化问题：

NSError *error;
NSData *returnData = [NSURLConnection sendSynchronousRequest: theRequest
                                           returningResponse: nil
                                                       error: &error];

NSLog(@"error = %@, \ndata = %@", error, returnData);

Answer 3

您还需要实现委托协议。（正如NSBum所说）

使用苹果example 此处显示的是将零件放在一起时返回的数据。：

    NSURLRequest *theRequest=[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.apple.com/"]
                                              cachePolicy:NSURLRequestUseProtocolCachePolicy
                                          timeoutInterval:60.0];

    // Create the NSMutableData to hold the received data.
    // receivedData is an instance variable declared elsewhere.
 receivedData = [NSMutableData dataWithCapacity: 0];

    // create the connection with the request
    // and start loading the data
    NSURLConnection *theConnection=[[NSURLConnection alloc] initWithRequest:theRequest delegate:self];
    if (!theConnection) {
        // Release the receivedData object.
        receivedData = nil;
            NSLog(@"FAIL " );
        // Inform the user that the connection failed.
    }



}

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

     NSLog(@" response %@", response);

    // This method is called when the server has determined that it
    // has enough information to create the NSURLResponse object.

    // It can be called multiple times, for example in the case of a
    // redirect, so each time we reset the data.

    // receivedData is an instance variable declared elsewhere.
    [receivedData setLength:0];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data
{
    // Append the new data to receivedData.
    // receivedData is an instance variable declared elsewhere.
    [receivedData appendData:data];

     NSLog(@" receivedData %@", receivedData);
}

receivedData不是本地的，而是在其他地方声明。（NSMutableData * receivedData;）

我没有使用这么多，所以如果不自己完全阅读文档，就无法进一步扩展;这是你需要做的。： - ）

NSUrlRequest不工作目标C.

3 个答案:

NSUrlRequest不工作​​目标C.

3 个答案:

NSUrlRequest不工作目标C.