轉載 --iOS實用小技巧(2)-生成txt文本

//不管是建立仍是寫入只需調用此段代碼便可 若是文件未建立 會進行建立操做
- (void)writeToFileWithTxt:(NSString *)string{
    dispatch_async(dispatch_get_global_queue(0, 0), ^{
        @synchronized (self) {
            //獲取沙盒路徑
            NSArray *paths  = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask,YES);
            //獲取文件路徑
            NSString *theFilePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"testLogs2.text"];
            //建立文件管理器
            NSFileManager *fileManager = [NSFileManager defaultManager];
            //若是文件不存在 建立文件
            if(![fileManager fileExistsAtPath:theFilePath]){
                NSString *str = @"日誌開始記錄\n";
                [str writeToFile:theFilePath atomically:YES encoding:NSUTF8StringEncoding error:nil];
            }
            NSLog(@"所寫內容=%@",string);
            NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:theFilePath];
            [fileHandle seekToEndOfFile];  //將節點跳到文件的末尾
            NSData* stringData  = [[NSString stringWithFormat:@"%@\n",string] dataUsingEncoding:NSUTF8StringEncoding];
            [fileHandle writeData:stringData]; //追加寫入數據
            [fileHandle closeFile];
        }
    });
}