ios - 如何放置时间戳，以便在保存时不会重复

Question

我想打个时间戳，这样当我保存应用程序时，我可以避免重复‖我正在使用代码

NSArray *directoryNames = [NSArray arrayWithObjects:@"hats",@"bottoms",@"right",@"left",nil];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents folder

    for (int i = 0; i < [directoryNames count] ; i++) {
        NSString *dataPath = [documentsDirectory stringByAppendingPathComponent:[directoryNames objectAtIndex:i]];
        if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath])
            [[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil error:nil]; //Create folder

        NSString *folderPath = [documentsDirectory stringByAppendingPathComponent:@"hats"]; // "right" is at index 2, per comments & code
        NSString *filePath = [folderPath stringByAppendingPathComponent:@"IMAGE_NAME_HERE.PNG"]; // you maybe want to incorporate a timestamp into the name to avoid duplicates
        NSData *imageData = UIImagePNGRepresentation(captureImage.image);
        [imageData writeToFile:filePath atomically:YES];
    }
} 

我如何放置时间戳或其他东西？我只是想停止重复所以它不需要是时间戳

Answer 1

您可以直接使用时间戳，不会重复。检查下面的代码

time_t unixTime = (time_t) [[NSDate date] timeIntervalSince1970];
NSString *timestamp=[NSString stringWithFormat:@"%ld",unixTime];