这是一个稍作改动的版本:

var regExp = /^.*(youtu.be\/|v\/|u\/\w\/|embed\/|watch\?v=|\&v=)([^#\&\?]{11,11}).*/;
var match = url.match(regExp);
if (match) if (match.length >= 2) return match[2];
// error

这假设代码总是11个字符。 我在ActionScript中使用这个，不确定在Javascript中是否支持{11,11}。还增加了对&v=....的支持(以防万一)

试试这个——

function getYouTubeIdFromURL($url) 
{
  $pattern = '/(?:youtube.com/(?:[^/]+/.+/|(?:v|e(?:mbed)?)/|.*[?&]v=)|youtu.be/)([^"&?/ ]{11})/i';
  preg_match($pattern, $url, $matches);

  return isset($matches[1]) ? $matches[1] : false;
}

/^.*(youtu.be\/|v\/|e\/|u\/\w+\/|embed\/|v=)([^#\&\?]*).*/

测试:

http://www.youtube.com/v/0zM3nApSvMg?fs=1&hl=en_US&rel=0 http://www.youtube.com/embed/0zM3nApSvMg?rel=0 http://www.youtube.com/watch?v=0zM3nApSvMg&feature=feedrec_grec_index http://www.youtube.com/watch?v=0zM3nApSvMg http://youtu.be/0zM3nApSvMg http://www.youtube.com/watch?v=0zM3nApSvMg#t=0m10s http://www.youtube.com/user/IngridMichaelsonVEVO#p/a/u/1/KdwsulMb8EQ http://youtu.be/dQw4w9WgXcQ http://www.youtube.com/embed/dQw4w9WgXcQ http://www.youtube.com/v/dQw4w9WgXcQ http://www.youtube.com/e/dQw4w9WgXcQ http://www.youtube.com/watch?v=dQw4w9WgXcQ http://www.youtube.com/?v=dQw4w9WgXcQ http://www.youtube.com/watch?feature=player_embedded&v=dQw4w9WgXcQ http://www.youtube.com/?feature=player_embedded&v=dQw4w9WgXcQ http://www.youtube.com/user/IngridMichaelsonVEVO#p/u/11/KdwsulMb8EQ http://www.youtube-nocookie.com/v/6L3ZvIMwZFM?version=3&hl=en_US&rel=0

受到另一个答案的启发。

我发现最好的解决方案(从2019年到2021年)是:

function YouTubeGetID(url){
   url = url.split(/(vi\/|v=|\/v\/|youtu\.be\/|\/embed\/)/);
   return (url[2] !== undefined) ? url[2].split(/[^0-9a-z_\-]/i)[0] : url[0];
}

我在这里找到的。

/*
* Tested URLs:
var url = 'http://youtube.googleapis.com/v/4e_kz79tjb8?version=3';
url = 'https://www.youtube.com/watch?feature=g-vrec&v=Y1xs_xPb46M';
url = 'http://www.youtube.com/watch?feature=player_embedded&v=Ab25nviakcw#';
url = 'http://youtu.be/Ab25nviakcw';
url = 'http://www.youtube.com/watch?v=Ab25nviakcw';
url = '<iframe width="420" height="315" src="http://www.youtube.com/embed/Ab25nviakcw" frameborder="0" allowfullscreen></iframe>';
url = '<object width="420" height="315"><param name="movie" value="http://www.youtube-nocookie.com/v/Ab25nviakcw?version=3&amp;hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube-nocookie.com/v/Ab25nviakcw?version=3&amp;hl=en_US" type="application/x-shockwave-flash" width="420" height="315" allowscriptaccess="always" allowfullscreen="true"></embed></object>';
url = 'http://i1.ytimg.com/vi/Ab25nviakcw/default.jpg';
url = 'https://www.youtube.com/watch?v=BGL22PTIOAM&feature=g-all-xit';
url = 'BGL22PTIOAM';
*/

你可以点击共享按钮并复制缩短URL。 例如: 这个YouTube视频的网址是https://www.youtube.com/watch?v=3R0fzCw3amM 但如果你点击分享按钮并复制缩短URL，你会得到这个https://youtu.be/3R0fzCw3amM

var video_url = document.getElementById('youtubediv').value;
        if(video_url!=""){
        ytid(video_url);
        document.getElementById("youtube").setAttribute("src","http://www.youtube.com/embed/"+ytid(video_url));
        }
        function ytid(video_url){
            var video_id = video_url.split('v=')[1];
            var ampersandPosition = video_id.indexOf('&');
            if(ampersandPosition != -1) {
                video_id = video_id.substring(0, ampersandPosition);
            }
            return video_id;
        }

我希望它能有所帮助