ios开发UDP协议发送广播寻找设备

代码链接 http://files.cnblogs.com/files/godlovexq/UDP.zip href="http://files.cnblogs.com/files/godlovexq/UDP.zip" target=_blank>


#import "AsyncUdpSocket.h"

#import <ifaddrs.h>

#import <arpa/inet.h>

//做udp 请求

-(void)MakeUDP

{

//实例化

AsyncUdpSocket *socket=[[AsyncUdpSocket alloc]initWithDelegate:self];

//启动本地端口

[socket localPort];

NSTimeInterval timeout=1000;//发送超时时间

NSString *request=@"dongqiangfei";//发送给服务器的内容

NSData *data=[NSData dataWithData:[request dataUsingEncoding:NSASCIIStringEncoding] ];

UInt16 port=6000;//端口

NSError *error;

//发送广播设置

[socket enableBroadcast:YES error:&error];

//@"10.10.60.255"

//把得到的目标ip 最后的数字更换为255（意思是搜索全部的）

NSArray *strArr=[[self getIPAddress] componentsSeparatedByString:@"."];

NSMutableArray *muArr = [NSMutableArray arrayWithArray:strArr];

[muArr replaceObjectAtIndex:(strArr.count-1) withObject:@"255"];

NSString *finalStr = [muArr componentsJoinedByString:@"."];//目标ip

/*

发送请求

sendData:发送的内容

toHost:目标的ip

port:端口号

timeOut:请求超时

*/

BOOL _isOK = [socket sendData :data toHost:[NSString stringWithFormat:@"%@",finalStr] port:port withTimeout:timeout tag:1];

if (_isOK) {

//udp请求成功

}else{

//udp请求失败

}

[socket receiveWithTimeout:1000 tag:0];//启动接收线程 - n?秒超时

NSLog(@"开始啦");

}

//接受信息

- (BOOL)onUdpSocket:(AsyncUdpSocket *)sock didReceiveData:(NSData *)data withTag:(long)tag fromHost:(NSString *)host port:(UInt16)port{

NSString* result;

result = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];

NSLog(@"%@",result);

NSLog(@"%@",host);

NSLog(@"收到啦");

return NO;

}

//接受失败

-(void)onUdpSocket:(AsyncUdpSocket *)sock didNotReceiveDataWithTag:(long)tag dueToError:(NSError *)error{

NSLog(@"没有收到啊 ");

}

//发送失败

-(void)onUdpSocket:(AsyncUdpSocket *)sock didNotSendDataWithTag:(long)tag dueToError:(NSError *)error{

NSLog(@"%@",error);

NSLog(@"没有发送啊");

}

//开始发送

-(void)onUdpSocket:(AsyncUdpSocket *)sock didSendDataWithTag:(long)tag{

NSLog(@"发送啦");

}

//关闭广播

-(void)onUdpSocketDidClose:(AsyncUdpSocket *)sock{

NSLog(@"关闭啦");

}

#pragma mark 获取当前IP

- (NSString *)getIPAddress {

NSString *address = @"error";

struct ifaddrs *interfaces = NULL;

struct ifaddrs *temp_addr = NULL;

int success = 0;

// retrieve the current interfaces - returns 0 on success

success = getifaddrs(&interfaces);

if (success == 0) {

// Loop through linked list of interfaces

temp_addr = interfaces;

while(temp_addr != NULL) {

if(temp_addr->ifa_addr->sa_family == AF_INET) {

// Check if interface is en0 which is the wifi connection on the iPhone

if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) {

// Get NSString from C String

address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];

}

}

temp_addr = temp_addr->ifa_next;

}

}

// Free memory

freeifaddrs(interfaces);

return address;

}