使“;nested"JavaScript代码更容易阅读

Javascript可以使用自定义算法来缩小，因此没有通用的方法来缩小它。

例如，我写了一个4kb的演示，其中js由一个自定义算法base85编码的字符串组成，其中包含一个自定义算法压缩版本的手动预处理，然后是clojue编译器压缩的javascript源代码。

我非常怀疑一个通用的工具可以自动将其解码为更易于人类阅读的形式。

你将不得不逐案工作，按照javascript正在做的步骤，这包括执行代码的eval。

请注意，在其他情况下，javascript代码可能是另一种语言的真正编译器的输出，其中所有高级符号信息已被删除(实际上它从未在javascript中存在，它仅以原始语言形式存在)。在这种情况下，你得到的是真正的"原始"javascript，你只能尝试缩进它，但这不会得到太多的可读性。

你可以找到的是通用的"美化器"，它只会重新缩进Javascript代码并添加一些空白，或者甚至可能是能够消除由特定的缩小器生成的代码的工具(特别是通用的缩小器:它们能够处理的Javascript越多，它们能够做的就越少……请记住，在Javascript中可以获得函数的源代码，因此依赖于函数的原始源代码的代码是有效的Javascript，不能在不改变其行为的情况下进行修改)。

如果您删除开头的eval并将最外层函数的返回值打印到控制台(console.log)，您可以看到正在执行的代码的缩小版本，但仍然更具可读性。

这是故意用一些工具来处理的，目的是为了保持原始的JavaScript 对脚本小子来说是不可读的。

   (function(p, a, c, k, e, d) {
    e = function(c) {
        return (c < a ? '' : e(parseInt(c / a))) + ((c = c % a) > 35 ? String.fromCharCode(c + 29) : c.toString(36))
    };
    if (!''.replace(/^/, String)) {
        while (c--) {
            d[e(c)] = k[c] || e(c)
        }
        k = [function(e) {
            return d[e]
        }];
        e = function() {
            return '''w+'
        };
        c = 1
    };
    while (c--) {
        if (k[c]) {
            p = p.replace(new RegExp('''b' + e(c) + '''b', 'g'), k[c])
        }
    }
    console.log(p);
    return p
}
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用jsBeautifier进一步处理这段代码会得到一个格式化的版本，可以在浏览器中调试。

(function() {
    var a = '0.com';
    var b = '//aaaaaa.com/path/ads/ads.js';
    var c = ' ';
    var d = 60;
    var e = 1;
    var f = true;
    var g = false;
    var h = null;
    var i = {
        route: 'get_pop',
        stid: '1920',
        sbid: '1',
        version: '9',
        page_url: encodeURI(document.location.href),
        p1: window.spot_code
    };
    var j = function(a, b, c) {
        var d = "";
        if (c) {
            var e = new Date();
            e.setTime(e.getTime() + (c * 60 * 1000));
            d = "; expires=" + e.toGMTString()
        } else d = "";
        document.cookie = a + "=" + b + d + "; path=/"
    };
    var k = function(a) {
        var b = a + "=";
        var c = document.cookie.split(';');
        for (var d = 0; d < c.length; d++) {
            var e = c[d];
            while (e.charAt(0) == ' ') e = e.substring(1, e.length);
            if (e.indexOf(b) == 0) return e.substring(b.length, e.length)
        }
        return null
    };
    var l = function(a) {
        var b = function(a, b) {
            while (a.parentNode) {
                a = a.parentNode;
                if (a.tagName != undefined && a.tagName.toLowerCase() === b) return a
            }
            return null
        };
        var e = (parent !== window) ? document.referrer : window.location.href;
        var l = n(i);
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            e = a.target.href;
            a.preventDefault()
        } else {
            var p = b(a.target, 'a');
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                e = p.href;
                a.preventDefault()
            }
        }
        var q = m().toLowerCase();
        if (navigator.userAgent.toLocaleLowerCase().indexOf('msie') == -1 && navigator.userAgent.toLocaleLowerCase().indexOf('trident') == -1) {
            var r = '<html><body><script>window.location="$url$";</script></body></html>'.replace('$url$', e);
            var s = o().encode(r);
            e = 'data:text/html;base64,$url$'.replace('$url$', s)
        }
        var t = k(c) == null ? 0 : parseInt(k(c));
        g = true;
        if (f) document.body.removeChild(h);
        j(c, t + 1, d);
        if (q.indexOf('chrome') != -1) {
            var u = document.createElement('a');
            u.href = e;
            var v = document.createEvent('MouseEvents');
            v.initMouseEvent('click', true, true, window, 0, 0, 0, 0, 0, false, false, false, false, true ? 1 : 0, null);
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        window.top.location.href = l
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        var a = navigator.userAgent,
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            b = /'brv[ :]+('d+)/g.exec(a) || [];
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        if (c[1] === 'Chrome') {
            b = a.match(/'b(OPR|Edge)'/('d+)/);
            if (b != null) return b.slice(1).join(' ').replace('OPR', 'Opera')
        }
        c = c[2] ? [c[1], c[2]] : [navigator.appName, navigator.appVersion, '-?'];
        if ((b = a.match(/version'/('d+)/i)) != null) c.splice(1, 1, b[1]);
        return c.join(' ')
    };
    var n = function(b) {
        var c = JSON.stringify(b);
        var d = o().encode(c);
        d = r() + d + r();
        d = d.replace(/'//g, '-');
        var e = 'http://' + a + '/' + d;
        return e
    };
    var o = function() {
        var a = "=",
            b = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/",
            c = "1.0";
        function d(a, c) {
            var d = b.indexOf(a.charAt(c));
            if (d === -1) throw "Cannot decode base64";
            return d
        }
        function e(b) {
            var c = 0,
                e, f, g = b.length,
                h = [];
            b = String(b);
            if (g === 0) return b;
            if (g % 4 !== 0) throw "Cannot decode base64";
            if (b.charAt(g - 1) === a) {
                c = 1;
                if (b.charAt(g - 2) === a) c = 2;
                g -= 4
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                    break;
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                    f = (d(b, e) << 18) | (d(b, e + 1) << 12);
                    h.push(String.fromCharCode(f >> 16));
                    break
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        }
        function f(a, b) {
            var c = a.charCodeAt(b);
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            if (arguments.length !== 1) throw "SyntaxError: exactly one argument required";
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                h = c.length - c.length % 3;
            if (c.length === 0) return c;
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                e = (f(c, d) << 16) | (f(c, d + 1) << 8) | f(c, d + 2);
                g.push(b.charAt(e >> 18));
                g.push(b.charAt((e >> 12) & 63));
                g.push(b.charAt((e >> 6) & 63));
                g.push(b.charAt(e & 63))
            }
            switch (c.length - h) {
                case 1:
                    e = f(c, d) << 16;
                    g.push(b.charAt(e >> 18) + b.charAt((e >> 12) & 63) + a + a);
                    break;
                case 2:
                    e = (f(c, d) << 16) | (f(c, d + 1) << 8);
                    g.push(b.charAt(e >> 18) + b.charAt((e >> 12) & 63) + b.charAt((e >> 6) & 63) + a);
                    break
            }
            return g.join("")
        }
        return {
            encode: g,
            decode: e
        }
    };
    var p = function(a, b) {
        var c, d, e;
        d = false;
        c = document.createElement('script');
        c.type = 'text/javascript';
        c.src = a;
        c.onload = c.onreadystatechange = function() {
            if (!d && (!this.readyState || this.readyState == 'loaded' || this.readyState == 'complete')) {
                d = true;
                if (b) b()
            }
        };
        c.onerror = function() {
            b()
        };
        e = document.getElementsByTagName('script')[0];
        e.parentNode.insertBefore(c, e)
    };
    var q = function(a, b) {
        if (b == undefined) {
            var c = document.head || document.getElementsByTagName('head')[0];
            var b = document.createElement('style');
            b.type = 'text/css';
            c.appendChild(b)
        }
        if (b.styleSheet) b.styleSheet.cssText = a;
        else b.appendChild(document.createTextNode(a));
        return b
    };
    var r = function() {
        var a = '';
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        return a
    };
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    var t = function() {
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        if (a >= e) return;
        if (f) {
            var b = document.body;
            var d = document.documentElement;
            var i = Math.max(b.scrollHeight, b.offsetHeight, d.clientHeight, d.scrollHeight, d.offsetHeight);
            var j = Math.max(b.scrollWidth, b.offsetWidth, d.clientWidth, d.scrollWidth, d.offsetWidth);
            var m = Math.floor((Math.random() * 10) + 1);
            var n = Math.floor((Math.random() * 10) + 1);
            var o = s(m) + new Date().getTime() + s(n);
            h = document.createElement('div');
            h.className = o;
            var p = '{display: block !important; ' + 'visibility: visible !important; ' + 'height: $height$px !important; ' + 'width: $width$px !important; ' + 'top: 0px !important; ' + 'left: 0px !important; ' + 'position: absolute !important; ' + 'cursor: default; ' + 'z-index: 999999 !important;}';
            var r = p.replace('$height$', i).replace('$width$', j);
            var t = q('.' + o + r);
            document.body.appendChild(h);
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                t = q('.' + o + b)
            };
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            else h.attachEvent('onclick', l)
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    p(b, function() {
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        else t()
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})();