在相同的局域网内,可以通过Udp协议进行数据的传输和接收,Udp协议与Http协议不同,Udp更加方便快捷,省去了很多步骤,但是也有很多传输问题,在局域网内小范围传输数据时Udp还是非常能够胜任的。
在iOS开发环境下,就要通过AsyncUdpSocket这个框架来进行Udp协议下的数据传输。
1.要添加AsyncUdpSocket框架文件到项目,并在需要使用Udp协议的类中加入其头文件
(这两个文件在网上可以搜到)
2.对Socket进行实例化,并初始化
NSError * error = Nil;
//使用IPv4初始化一个Socket
activeSocket = [[AsyncUdpSocketalloc] initIPv4];
//设置委托为自身
[activeSocketsetDelegate:self];
//PORT_ACTIVE为发送端口
[activeSocketbindToPort:PORT_ACTIVEerror:& error];
//允许广播信息
[activeSocketenableBroadcast:YESerror:& error];
//允许接受信息
[activeSocketreceiveWithTimeout:-1tag:0];
3.在类中加入AsyncUdpSocket的委托
#pragma mark - AsyncUdpSocket Delegate
- (BOOL)onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port
{
returnYES;
}
- (void)onUdpSocket:(AsyncUdpSocket *)sock didNotReceiveDataWithTag:(long)tag dueToError:(NSError *)error
{
}
- (void)onUdpSocket:(AsyncUdpSocket *)sock didSendDataWithTag:(long)tag
{
}
- (void)onUdpSocket:(AsyncUdpSocket *)sock didNotSendDataWithTag:(long)tag dueToError:(NSError *)error
{
}
- (void)onUdpSocketDidClose:(AsyncUdpSocket *)sock
{
}
4.发送数据
//theMessage为NSString,为需要发送的数据
NSData * data = [theMessage dataUsingEncoding:NSASCIIStringEncoding] ;
BOOL result = NO;
//开始发送
//pcHost为接收方的ip地址,255.255.255.255为向全域广播
//thePort为发送端口
result = [theSocket sendData:data
toHost:pcHost
port:thePort
withTimeout:1000
tag:0];
if (!result) {
NSLog(@"send failed");
}
else{
NSLog(@"send succeed");
}
5.接收数据
接收数据的实现在委托中
- (BOOL)onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port
{
//重新设置接收时间
[sock receiveWithTimeout:-1tag:0];
//info就为接收到的数据
NSString *info=[[NSStringalloc] initWithData:data encoding: NSUTF8StringEncoding];
returnYES;
}