如何识别多个NSURLConnection在多个时完成加载？

Question

启动多个NSURLConnections(在单个UIViewController中)以收集不同类型的数据.当他们返回(-connectionDidFinishLoading)时,我想对数据进行处理,具体取决于已到达的数据类型.但有一个问题,我怎么知道NSURLConnection返回了什么？我需要知道,所以我可以采取特定的数据类型的行动.(例如,如果是twitter xml数据,则显示Twitter更新)(例如,如果是照片则显示图像)

人们通常如何解决这个问题？

Answer 1

您保留指向委托中两个连接的指针,并将它们与和中的connection参数进行比较connection:didReceiveData:connectiondidFinishLoading:

例如:

@interface Foo : NSObject {
    NSURLConnection *connection1;
    NSURLConnection *connection2;
}

和

connection1 = [NSURLConnection connectionWithRequest:request1 delegate:self];
connection2 = [NSURLConnection connectionWithRequest:request2 delegate:self];

和

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    if(connection == connection1) {
        // Connection 1
    } else if(connection == connection2) {
        // Connection 2
    }
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    if(connection == connection1) {
        // Connection 1
    } else if(connection == connection2) {
        // Connection 2
    }
}