如何在所有现代浏览器中检测页面缩放级别?虽然这篇文章讲述了如何在IE7和IE8中做到这一点,但我找不到一个好的跨浏览器解决方案。 Firefox存储页面缩放级别以供将来访问。在第一页加载,我能得到缩放级别吗?在某个地方,我读到当页面加载后发生缩放变化时,它是有效的。 有办法捕捉'缩放'事件吗?

我需要这个,因为我的一些计算是基于像素的,他们可能会在放大时波动。


@tfl给出的修改样本

放大时,此页面会提示不同的高度值。(jsFiddle)

<html>
    <head>
        <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.1/jquery.min.js" type="text/javascript"/></script>
    </head>
    <body>
        <div id="xy" style="border:1px solid #f00; width:100px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque sollicitudin tortor in lacus tincidunt volutpat. Integer dignissim imperdiet mollis. Suspendisse quis tortor velit, placerat tempor neque. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Praesent bibendum auctor lorem vitae tempor. Nullam condimentum aliquam elementum. Nullam egestas gravida elementum. Maecenas mattis molestie nisl sit amet vehicula. Donec semper tristique blandit. Vestibulum adipiscing placerat mollis.</div>
        <button onclick="alert($('#xy').height());">Show</button>
    </body>
</html>

当前回答

function supportFullCss3()
{
    var div = document.createElement("div");
    div.style.display = 'flex';
    var s1 = div.style.display == 'flex';
    var s2 = 'perspective' in div.style;

    return (s1 && s2);
};

function getZoomLevel()
{
    var screenPixelRatio = 0, zoomLevel = 0;

    if(window.devicePixelRatio && supportFullCss3())
        screenPixelRatio = window.devicePixelRatio;
    else if(window.screenX == '0')
        screenPixelRatio = (window.outerWidth - 8) / window.innerWidth;
    else
    {
        var scr = window.frames.screen;
        screenPixelRatio = scr.deviceXDPI / scr.systemXDPI;
    }

    //---------------------------------------
    if (screenPixelRatio <= .11){ //screenPixelRatio >= .01 &&
      zoomLevel = "-7";
    } else if (screenPixelRatio <= .25) {
      zoomLevel = "-6";
    }else if (screenPixelRatio <= .33) {
      zoomLevel = "-5.5";
    } else if (screenPixelRatio <= .40) {
      zoomLevel = "-5";
    } else if (screenPixelRatio <= .50) {
      zoomLevel = "-4";
    } else if (screenPixelRatio <= .67) {
      zoomLevel = "-3";
    } else if (screenPixelRatio <= .75) {
      zoomLevel = "-2";
    } else if (screenPixelRatio <= .85) {
      zoomLevel = "-1.5";
    } else if (screenPixelRatio <= .98) {
      zoomLevel = "-1";
    } else if (screenPixelRatio <= 1.03) {
      zoomLevel = "0";
    } else if (screenPixelRatio <= 1.12) {
      zoomLevel = "1";
    } else if (screenPixelRatio <= 1.2) {
      zoomLevel = "1.5";
    } else if (screenPixelRatio <= 1.3) {
      zoomLevel = "2";
    } else if (screenPixelRatio <= 1.4) {
      zoomLevel = "2.5";
    } else if (screenPixelRatio <= 1.5) {
      zoomLevel = "3";
    } else if (screenPixelRatio <= 1.6) {
      zoomLevel = "3.3";
    } else if (screenPixelRatio <= 1.7) {
      zoomLevel = "3.7";
    } else if (screenPixelRatio <= 1.8) {
      zoomLevel = "4";
    } else if (screenPixelRatio <= 1.9) {
      zoomLevel = "4.5";
    } else if (screenPixelRatio <= 2) {
      zoomLevel = "5";
    } else if (screenPixelRatio <= 2.1) {
      zoomLevel = "5.2";
    } else if (screenPixelRatio <= 2.2) {
      zoomLevel = "5.4";
    } else if (screenPixelRatio <= 2.3) {
      zoomLevel = "5.6";
    } else if (screenPixelRatio <= 2.4) {
      zoomLevel = "5.8";
    } else if (screenPixelRatio <= 2.5) {
      zoomLevel = "6";
    } else if (screenPixelRatio <= 2.6) {
      zoomLevel = "6.2";
    } else if (screenPixelRatio <= 2.7) {
      zoomLevel = "6.4";
    } else if (screenPixelRatio <= 2.8) {
      zoomLevel = "6.6";
    } else if (screenPixelRatio <= 2.9) {
      zoomLevel = "6.8";
    } else if (screenPixelRatio <= 3) {
      zoomLevel = "7";
    } else if (screenPixelRatio <= 3.1) {
      zoomLevel = "7.1";
    } else if (screenPixelRatio <= 3.2) {
      zoomLevel = "7.2";
    } else if (screenPixelRatio <= 3.3) {
      zoomLevel = "7.3";
    } else if (screenPixelRatio <= 3.4) {
      zoomLevel = "7.4";
    } else if (screenPixelRatio <= 3.5) {
      zoomLevel = "7.5";
    } else if (screenPixelRatio <= 3.6) {
      zoomLevel = "7.6";
    } else if (screenPixelRatio <= 3.7) {
      zoomLevel = "7.7";
    } else if (screenPixelRatio <= 3.8) {
      zoomLevel = "7.8";
    } else if (screenPixelRatio <= 3.9) {
      zoomLevel = "7.9";
    } else if (screenPixelRatio <= 4) {
      zoomLevel = "8";
    } else if (screenPixelRatio <= 4.1) {
      zoomLevel = "8.1";
    } else if (screenPixelRatio <= 4.2) {
      zoomLevel = "8.2";
    } else if (screenPixelRatio <= 4.3) {
      zoomLevel = "8.3";
    } else if (screenPixelRatio <= 4.4) {
      zoomLevel = "8.4";
    } else if (screenPixelRatio <= 4.5) {
      zoomLevel = "8.5";
    } else if (screenPixelRatio <= 4.6) {
      zoomLevel = "8.6";
    } else if (screenPixelRatio <= 4.7) {
      zoomLevel = "8.7";
    } else if (screenPixelRatio <= 4.8) {
      zoomLevel = "8.8";
    } else if (screenPixelRatio <= 4.9) {
      zoomLevel = "8.9";
    } else if (screenPixelRatio <= 5) {
      zoomLevel = "9";
    }else {
      zoomLevel = "unknown";
    }

    return zoomLevel;
};

其他回答

这可能会或可能不会帮助任何人,但我有一个页面,我不能得到正确的中心,无论什么Css技巧我尝试了,所以我写了一个JQuery文件呼叫中心页面:

问题发生在浏览器的缩放级别,页面会根据您的100%,125%,150%等进行移动。

下面的代码位于一个名为centerpage.js的JQuery文件中。

从我的页面,我必须链接到JQuery和这个文件才能让它工作,即使我的主页已经有一个链接到JQuery。

<title>Home Page.</title>
<script src="Scripts/jquery-1.7.1.min.js"></script>
<script src="Scripts/centerpage.js"></script>

centerpage.js:

// centering page element
function centerPage() {
    // get body element
    var body = document.body;

    // if the body element exists
    if (body != null) {
        // get the clientWidth
        var clientWidth = body.clientWidth;

        // request data for centering
        var windowWidth = document.documentElement.clientWidth;
        var left = (windowWidth - bodyWidth) / 2;

        // this is a hack, but it works for me a better method is to determine the 
        // scale but for now it works for my needs
        if (left > 84) {
            // the zoom level is most likely around 150 or higher
            $('#MainBody').removeClass('body').addClass('body150');
        } else if (left < 100) {
            // the zoom level is most likely around 110 - 140
            $('#MainBody').removeClass('body').addClass('body125');
        }
    }
}


// CONTROLLING EVENTS IN jQuery
$(document).ready(function() {
    // center the page
    centerPage();
});

如果你想让一个面板居中:

// centering panel
function centerPanel($panelControl) {
    // if the panel control exists
    if ($panelControl && $panelControl.length) {
        // request data for centering
        var windowWidth = document.documentElement.clientWidth;
        var windowHeight = document.documentElement.clientHeight;
        var panelHeight = $panelControl.height();
        var panelWidth = $panelControl.width();

        // centering
        $panelControl.css({
            'position': 'absolute',
            'top': (windowHeight - panelHeight) / 2,
            'left': (windowWidth - panelWidth) / 2
        });

        // only need force for IE6
        $('#backgroundPanel').css('height', windowHeight);
    }
}

这可以检测比例。

html代码:

<body id="blog">

js:

function scale(){
return Math.round(100/(d.getElementById('blog').offsetWidth/d.getElementById('blog').getBoundingClientRect().width))/100;
}

缩放因子和比例不能相互混淆。用户控制“缩放”; “scale”是一个CSS转换。然而,11年零10个月前,understack指出:

基本上我想知道DIV在100%缩放时的尺寸。

这个是这样的。我将其与@media查询一起使用,以检测JavaScript中的设备缩放,即360x720可能应用0.5缩放;720 x360, 0.75。

var d=document;

在移动设备(Chrome for Android或Opera mobile)上,你可以通过window.visualViewport.scale来检测缩放。 https://developer.mozilla.org/en-US/docs/Web/API/Visual_Viewport_API

在Safari上检测:document.documentElement.clientWidth / window。innerWidth(如果设备上没有缩放则返回1)。

在Internet Explorer 7、8和9中,这是有效的:

function getZoom() {
    var screen;

    screen = document.frames.screen;
    return ((screen.deviceXDPI / screen.systemXDPI) * 100 + 0.9).toFixed();
}

添加“+0.9”是为了防止舍入错误(否则,当浏览器缩放分别设置为105%和110%时,您将得到104%和109%)。

在IE6中不存在缩放,所以没有必要检查缩放。

在Chrome

var ratio = (screen.availWidth / document.documentElement.clientWidth);
var zoomLevel = Number(ratio.toFixed(1).replace(".", "") + "0");