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Objective-C实现UDP传输系统源码示例

以下是一个简单的Objective-C实现UDP传输系统的示例，包含客户端和服务器代码。该示例适用于macOS环境，使用了Foundation框架进行开发。

UDP服务器代码

UDPServer.m

#import 
   

@interface UDPServer : NSObject
{
    NSRunLoop *runLoop;
    NSSocketRef socket;
    NSString *host;
    uint16_t port;
}
@property (nonatomic, retain) NSRunLoop *runLoop;
@property (nonatomic, assign) NSSocketRef socket;
@property (nonatomic, copy) NSString *host;
@property (nonatomic, assign) uint16_t port;
- (id)initWithHost:(NSString *)host port:(uint16_t)port;
- (void)run;
- (void)sendData:(NSData *)data;
- (void)close;
@end

@implementation UDPServer
- (id)initWithHost:(NSString *)host port:(uint16_t)port
{
    if (self = [super init])
    {
        self.host = host;
        self.port = port;
        self.runLoop = [NSRunLoop currentRunLoop];
        self.socket = NULL;
        
        // 创建UDP socket
        self.socket = socket(AF_INET, SOCK_DGRAM, 0);
        if (!self.socket)
        {
            NSLog(@"无法创建UDP socket");
            return nil;
        }
        
        // 绑定IP和端口
        struct sockaddr_in addr;
        addr.sin_family = AF_INET;
        addr.sin_port = htons((uint16_t)port);
        addr.sin_addr = *(struct sockaddr *)&host;
        
        if (bind(self.socket, (struct sockaddr *)&addr, sizeof(addr)) == -1)
        {
            NSLog(@"绑定失败");
            return nil;
        }
        
        // 启动RunLoop
        [self.runLoop addPort:socket forRunLoopMode:NSRunLoopCommonMode];
        return self;
    }
    
    return nil;
}
- (void)run
{
    // 处理接受的数据
    while (true)
    {
        char buffer[1024];
        DataRef dataRef;
        read(self.socket, (char *)buffer, sizeof(buffer), &dataRef);
        
        if (dataRef.length > 0)
        {
            // 处理接收到的数据
            // ... 根据实际需求添加处理逻辑 ...
        }
    }
}
- (void)sendData:(NSData *)data
{
    if (self.socket)
    {
        if (send(self.socket, data.bytes, data.length, 0, NULL) == -1)
        {
            NSLog(@"发送失败");
        }
    }
    else
    {
        NSLog(@"socket已关闭");
    }
}
- (void)close
{
    if (self.socket)
    {
        close(self.socket);
        self.socket = NULL;
    }
    
    // 停止RunLoop
    [self.runLoop removePort:self.socket forRunLoopMode:NSRunLoopCommonMode];
    [self.runLoop release];
    self.runLoop = nil;
}

UDP客户端代码

UDPClient.m

#import 
   

@interface UDPClient : NSObject
{
    NSRunLoop *runLoop;
    NSSocketRef socket;
    NSString *host;
    uint16_t port;
}
@property (nonatomic, retain) NSRunLoop *runLoop;
@property (nonatomic, assign) NSSocketRef socket;
@property (nonatomic, copy) NSString *host;
@property (nonatomic, assign) uint16_t port;
- (id)initWithHost:(NSString *)host port:(uint16_t)port;
- (void)run;
- (void)sendData:(NSData *)data;
- (void)close;
@end

@implementation UDPClient
- (id)initWithHost:(NSString *)host port:(uint16_t)port
{
    if (self = [super init])
    {
        self.host = host;
        self.port = port;
        self.runLoop = [NSRunLoop currentRunLoop];
        self.socket = NULL;
        
        // 创建UDP socket
        self.socket = socket(AF_INET, SOCK_DGRAM, 0);
        if (!self.socket)
        {
            NSLog(@"无法创建UDP socket");
            return nil;
        }
        
        // 连接到服务器
        struct sockaddr_in addr;
        addr.sin_family = AF_INET;
        addr.sin_port = htons((uint16_t)port);
        addr.sin_addr = *(struct sockaddr *)&host;
        
        if (connect(self.socket, (struct sockaddr *)&addr, sizeof(addr)) == -1)
        {
            NSLog(@"连接失败");
            return nil;
        }
        
        // 启动RunLoop
        [self.runLoop addPort:socket forRunLoopMode:NSRunLoopCommonMode];
        return self;
    }
    
    return nil;
}
- (void)run
{
    // 处理发送数据
    while (true)
    {
        char buffer[1024];
        NSString *inputString = [NSString stringWithCString(readline(&buffer, sizeof(buffer), NULL))];
        
        if (inputString.length > 0)
        {
            // 将输入字符串转换为数据
            NSData *data = [inputString dataUsingEncoding:NSUTF8StringEncoding];
            [self sendData:data];
        }
    }
}
- (void)sendData:(NSData *)data
{
    if (self.socket)
    {
        if (send(self.socket, data.bytes, data.length, 0, NULL) == -1)
        {
            NSLog(@"发送失败");
        }
    }
    else
    {
        NSLog(@"socket已关闭");
    }
}
- (void)close
{
    if (self.socket)
    {
        close(self.socket);
        self.socket = NULL;
    }
    
    // 停止RunLoop
    [self.runLoop removePort:self.socket forRunLoopMode:NSRunLoopCommonMode];
    [self.runLoop release];
    self.runLoop = nil;
}

开发说明

该示例实现了一个简单的UDP数据传输系统，适用于macOS环境。开发过程中使用了Foundation框架来处理网络通信相关任务。服务器端通过bind和listen等函数接收数据，客户端则通过connect和send函数进行数据发送。

项目结构

运行环境

• 操作系统：macOS 10.12 及以上版本
• 开发工具：Xcode 8 或更高版本
• 依赖项：Foundation框架

使用方法

如有问题，请参考相关文档或社区，确保环境配置正确并遵循苹果开发规范。