iPhone開發之網絡編程 AsyncSocket
iphone的CFNetwork編程比較艱深。使用AsyncSocket開源庫來開發相對較簡單,下面介紹一些簡單的使用,并給出一個簡單的實現模板,只要添加自己的處理代碼就可以使用了。
項目主頁:http://code.google.com/p/cocoaasyncsocket/
一.項目添加ASyncSocket
1.下載ASyncSocket庫源碼
2.把ASyncSocket庫源碼加入項目
3.在項目增加CFNetwork框架
二.功能介紹
1.在需要聯接地方使用connectToHost聯接服務器
其中initWithDelegate的參數中self是必須。這個對象指針中的各個Socket響應的函數將被ASyncSocket所調用.
asyncSocket = [[AsyncSocket alloc] initWithDelegate:self];
NSError *err = nil;
if(![asyncSocket connectToHost:host on:port error:&err])
{
NSLog(@"Error: %@", err);
}
2.增加Socket響應事件
因為initWithDelegate把將當前對象傳遞進去,這樣只要在當前對象方法實現相應方法.
關于NSData對象
無論SOCKET收發都采用NSData對象.它的定義是
NSData主要是帶一個(id)data指向的數據空間和長度 length.
NSString 轉換成NSData 對象
NSData* xmlData = [@"testdata" dataUsingEncoding:NSUTF8StringEncoding];
NSData 轉換成NSString對象
NSData * data;
NSString *result = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
3.發送數據
AsyncSocket writeData 方法來發送數據,它有如下定義
- (void)writeData:(NSData *)data withTimeout:(NSTimeInterval)timeout tag:(long)tag;
以下是一個實例語句.
NSData* aData= [@"test data" dataUsingEncoding: NSUTF8StringEncoding];
[sock writeData:aData withTimeout:-1 tag:1];
4.接收Socket數據.
在onSocket重載函數,有如定義采用是專門用來處理SOCKET的接收數據的.
-(void) onSocket:(AsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag
在中間將其轉換成NSString進行顯示.
NSString* aStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"===%@",aStr);
[aStr release];
三.實現模板,將直接的代碼添加進入就可以使用了
#import "AsyncSocket.h" #define theEndTag 255 @implementation SocketComm //初始話,創建socket - (id) init { self = [super init]; if (self != nil) { _sock = [[AsyncSocket alloc] initWithDelegate:self]; [_sock setRunLoopModes:[NSArray arrayWithObject:NSRunLoopCommonModes]]; } return self; } //發送數據 -(void)writeDataOnMainThread:(id)string { NSData *cmdData = [string dataUsingEncoding:NSUTF8StringEncoding] [_sock writeData:data withTimeout:-1 tag:0]; } //打開 - (NSInteger)SocketOpen:(NSString*)addr port:(NSInteger)port { if (![_sock isConnected]) { [_sock connectToHost:addr onPort:port withTimeout:timeout error:&err]; NSLog(@"connect to Host:%@ Port:%d",addr,port); } return 0; } //寫數據 - (NSInteger)SocketWrite:(NSString*)cmd level:(NSInteger)level { if ([_sock isConnected]) { //處理發送數據,加入隊列等待發送 } else { NSLog(@"Offline!"); } return 0; } //關閉 - (NSInteger)SocketClose { if ([_sock isConnected]) { [_sock writeData:Data withTimeout:-1 tag:theEndTag]; [_sock disconnectAfterReadingAndWriting]; } return 0; } #pragma mark - #pragma mark Delegate - (void)onSocket:(AsyncSocket *)sock willDisconnectWithError:(NSError *)err { NSLog(@"willDisconnectWithError:%@",err); } - (void)onSocketDidDisconnect:(AsyncSocket *)sock { NSLog(@"onSocketDidDisconnect"); } - (void)onSocket:(AsyncSocket *)sock didConnectToHost:(NSString *)host port:(UInt16)port { NSLog(@"didConnectToHost"); //這是異步返回的連接成功, [sock readDataWithTimeout:-1 tag:0]; } - (void)onSocket:(AsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag { NSString *msg = [[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] autorelease]; if(msg) { //處理受到的數據 } else { NSLog(@"Error converting received data into UTF-8 String"); } [sock readDataWithTimeout:-1 tag:0]; } - (void)onSocket:(AsyncSocket *)sock didWriteDataWithTag:(long)tag { NSLog(@"didWriteDataWithTag:%d",tag); } @end