Question

我必须使用套接字编程为iOS创建聊天应用，我的IP地址为192.168.0.57:9300。我使用了Raywenderlich套接字编程示例，接收数据正常工作但发送不工作，没有任何错误或崩溃。我的代码如下。

打开流的代码

- (void) initNetworkCommunication {

    CFReadStreamRef readStream;
    CFWriteStreamRef writeStream;
    CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)@"192.168.0.57", 9300, &readStream, &writeStream);

    inputStream = (NSInputStream *)readStream;
    outputStream = (NSOutputStream *)writeStream;
    [inputStream setDelegate:self];
    [outputStream setDelegate:self];
    [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
    [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
    [inputStream open];
    [outputStream open];    
}

发送数据的代码

- (IBAction)sendMessage:(id)sender
{
        NSString *response  = @"lets start chat";
        NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]];
        [outputStream write:[data bytes] maxLength:[data length]]; 
}

代表

- (void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent {

    NSLog(@"stream event %i", streamEvent);

    switch (streamEvent) {

        case NSStreamEventOpenCompleted:
            NSLog(@"Stream opened");
            break;
        case NSStreamEventHasBytesAvailable:

            if (theStream == inputStream) {

                uint8_t buffer[1024];
                int len;

                while ([inputStream hasBytesAvailable]) {
                    len = [inputStream read:buffer maxLength:sizeof(buffer)];
                    if (len > 0) {

                        NSString *output = [[NSString alloc] initWithBytes:buffer length:len encoding:NSASCIIStringEncoding];

                        if (nil != output) {

                            NSLog(@"\nreciving data------%@,buffer);

                            [self messageReceived:output];

                        }
                    }
                }
            }
            break;


        case NSStreamEventErrorOccurred:

            NSLog(@"Can not connect to the host!");
            break;

        case NSStreamEventEndEncountered:

            [theStream close];
            [theStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            [theStream release];
            theStream = nil;

            break;
        default:
            NSLog(@"Unknown event");
    }

}
Message sending
    - (void) messageReceived:(NSString *)message {

        [self.messages addObject:message];
        [self.tView reloadData];
        NSIndexPath *topIndexPath = [NSIndexPath indexPathForRow:messages.count-1 
                                                       inSection:0];
        [self.tView scrollToRowAtIndexPath:topIndexPath 
                          atScrollPosition:UITableViewScrollPositionMiddle 
                                  animated:YES];

    }

请提供我的建议。

Answer 1

您应该在回复的末尾添加“\ n”，如下所示：

- (IBAction)sendMessage:(id)sender
{
        NSString *response  = @"lets start chat\n";
        ////your code
}

这对我有用，但我的问题是我无法使用函数(void)stream:(NSStream *)theStream handleEvent:(NSStreamEvent)streamEvent

接收数据

Answer 2

我有类似的问题。通过在字符串中添加换行符和换行符来解决它。

- (IBAction)sendMessage:(id)sender {

        NSString *response  = @"lets start chat\r\n\r\n";
        NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]];
        [outputStream write:[data bytes] maxLength:[data length]]; 
}

Answer 3

我发现写一个单独的帖子为我解决了这个问题有道理，因为人们不应该在主线上做网络操作这是我的代码：

dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0), ^(void) {
    NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]];
    NSInteger len = [outputStream write:[data bytes] maxLength:[data length]];
    NSLog(@"Len = %ld", len);
});

需要注意的另一点是NSStreamEventOpenCompleted事件被调用两次。一旦打开每个输入和输出流。因此，需要注意不要在事件发生之前写入输出流。

如何使用NSOutputStream通过套接字发送NSString

3 个答案: