这是我的方法。一个有效的示例在此jsFiddle中。
var min_w = 300; // minimum video width allowedvar vid_w_orig; // original video dimensionsvar vid_h_orig;jQuery(function() { // runs after DOM has loaded vid_w_orig = parseInt(jQuery('video').attr('width')); vid_h_orig = parseInt(jQuery('video').attr('height')); $('#debug').append("<p>DOM loaded</p>"); jQuery(window).resize(function () { resizeToCover(); }); jQuery(window).trigger('resize');});function resizeToCover() { // set the video viewport to the window size jQuery('#video-viewport').width(jQuery(window).width()); jQuery('#video-viewport').height(jQuery(window).height()); // use largest scale factor of horizontal/vertical var scale_h = jQuery(window).width() / vid_w_orig; var scale_v = jQuery(window).height() / vid_h_orig; var scale = scale_h > scale_v ? scale_h : scale_v; // don't allow scaled width < minimum video width if (scale * vid_w_orig < min_w) {scale = min_w / vid_w_orig;}; // now scale the video jQuery('video').width(scale * vid_w_orig); jQuery('video').height(scale * vid_h_orig); // and center it by scrolling the video viewport jQuery('#video-viewport').scrollLeft((jQuery('video').width() - jQuery(window).width()) / 2); jQuery('#video-viewport').scrollTop((jQuery('video').height() - jQuery(window).height()) / 2); // debug output jQuery('#debug').html("<p>win_w: " + jQuery(window).width() + "</p>"); jQuery('#debug').append("<p>win_h: " + jQuery(window).height() + "</p>"); jQuery('#debug').append("<p>viewport_w: " + jQuery('#video-viewport').width() + "</p>"); jQuery('#debug').append("<p>viewport_h: " + jQuery('#video-viewport').height() + "</p>"); jQuery('#debug').append("<p>video_w: " + jQuery('video').width() + "</p>"); jQuery('#debug').append("<p>video_h: " + jQuery('video').height() + "</p>"); jQuery('#debug').append("<p>vid_w_orig: " + vid_w_orig + "</p>"); jQuery('#debug').append("<p>vid_h_orig: " + vid_h_orig + "</p>"); jQuery('#debug').append("<p>scale: " + scale + "</p>");};#video-viewport { position: absolute; top: 0; overflow: hidden; z-index: -1; }#debug { position: absolute; top: 0; z-index: 100; color: #fff; font-size: 12pt;}<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script><div id="video-viewport"> <video autoplay controls preload width="640" height="360"> <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.mp4"type="video/mp4" /> <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.webm"type="video/webm" /> <source src="http://www.quirksmode.org/html5/videos/big_buck_bunny.ogv"type="video/webm" /> </video></div><div id="debug"></div>
