Question

我只是想知道当jQuery不支持opacity时如何在IE浏览器中生成淡入淡出效果？动画opacity是他们在Firefox和Chrome等其他浏览器中淡出的方式。我进入了代码，但老实说，我找不到任何可以理解的东西！

Answer 1

从jquery源代码，它们基本上检测是否支持不透明度，如果不支持，则使用IEs alpha filter

if ( !jQuery.support.opacity ) {
jQuery.cssHooks.opacity = {
    get: function( elem, computed ) {
        // IE uses filters for opacity
        return ropacity.test( (computed && elem.currentStyle ? elem.currentStyle.filter : elem.style.filter) || "" ) ?
            ( parseFloat( RegExp.$1 ) / 100 ) + "" :
            computed ? "1" : "";
    },

    set: function( elem, value ) {
        var style = elem.style,
            currentStyle = elem.currentStyle;

        // IE has trouble with opacity if it does not have layout
        // Force it by setting the zoom level
        style.zoom = 1;

        // Set the alpha filter to set the opacity
        var opacity = jQuery.isNaN( value ) ?
            "" :
            "alpha(opacity=" + value * 100 + ")",
            filter = currentStyle && currentStyle.filter || style.filter || "";

        style.filter = ralpha.test( filter ) ?
            filter.replace( ralpha, opacity ) :
            filter + " " + opacity;
    }
};
}

Answer 2

使用以下样式filter:alpha(opacity=40)

IE8如何在IE8及以下版本中“淡出”？

2 个答案: