Question

我需要从在线视频托管网站（即YouTube，DailyMotion，vimeo等）下载视频到我的iOS应用程序。

最近，当用户尝试播放其中的任何视频时，我会从UIWebView获取视频网址。获得资源网址（保存在某个在线路径的视频网址）并尝试下载后。

我是通过以下内容在YouTube上完成的：

NSString *resourceUrlStr ;
NSString *urlStr  = @"function getURL() { return document.getElementsByTagName('VIDEO')[0].src; } getURL();";

 resourceUrlStr = [myWebViewObject stringByEvaluatingJavaScriptFromString: urlStr];

此内容仅适用于YouTube视频，其中resourceUrlStr为我提供了视频资源的网址。

但是当我为DailyMotion＆amp;其他视频托管网站，它不会返回我的资源视频网址。

任何猜测？还是想法？

Answer 1

有几种技术可以执行它。

我喜欢的技巧是，当WebView中的播放器开始播放视频时您需要在下面设置通知代码：

-(void)viewWillAppear:(BOOL)animated{

    [super viewWillAppear:YES];


   [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(myVideoPlayedInFullscreenFirstTime:)
                                                 name:@"AVPlayerItemBecameCurrentNotification"
                                               object:nil];
}


-(void)myVideoPlayedInFullscreenFirstTime:(NSNotification*)aNotification {

    AVPlayerItem *playerItem = [aNotification object];
    if(playerItem == nil) return;
    // Break down the AVPlayerItem to get to the path
    AVURLAsset *asset = (AVURLAsset*)[playerItem asset];
    NSURL *downloadebaleVideoUrl = [asset URL];

/* now, You can download video by above URL.
In some cases it will give you “.m3u” file location. 
You can go through it & get All videos from that list.
For DailyMotion there is one library on GitHub:
[For DailyMotion](https://github.com/oikyn/ExtractVideoURLManager)

*/
}

Answer 2

#KunalParekh建议的Swift版解决方案是：

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(true)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(self.myVideoPlayedInFullscreenFirstTime), name: "AVPlayerItemBecameCurrentNotification", object: nil)
}

func myVideoPlayedInFullscreenFirstTime(aNotification: NSNotification) {
    var playerItem = aNotification.object
    if playerItem == nil {
        return
    }

    let asset:AVURLAsset = playerItem?.asset as! AVURLAsset
    var downloadebaleVideoUrl = asset.URL
    print("downloadable video url is: \(downloadebaleVideoUrl)")
}

请记得导入AVFoundation

从DailyMotion视频＆amp;获取可下载的URL（资源URL）。其他网站？

2 个答案: