小编mon*_*ist的帖子

我有一个URL,我想在FancyBox(或任何其他叠加类型弹出窗口)中打开.我不知道URL是否好,所以我想测试一下.如果无效 - 我不会将fancyBox插件附加到该特定URL,它将只是一个常规链接.如何在插入插件之前测试URL？尝试做类似的事情:

$("a.overlay").each(function() {
    var xhr = $.get(this.href, function(data, status) {
        // never executed in case of a failed request
    });
    if (xhr.status && xhr.status === 404)) {
        // not good, do nothing
    } else {
        // can attach plugin here
    }
});

问题是,xhr并不总是定义,因为JS不等待请求完成.类似地,我不能使用回调函数,因为它似乎没有执行,以防请求失败(我可以在Firebug中看到它,但这不是很有用).

谢谢,祝大家周末愉快.

我是JavaScript的新手,因为我来自强类型语言,所以我选择了TypeScript.

我想知道发生了什么变量red在Red getter这个代码.它会在每次调用时重新创建(如in Green getter)还是每次创建一次并使用？哪个最好？

class Color {
    public R: number;
    public G: number;
    public B: number;
    public A: number;

    static get Red(): Color {
        var red = new Color(255, 0, 0);
        Color.Red = function() { return red; }
        return red;
    }

    static get Green(): Color {
        return new Color(0, 255, 0);
    }

    constructor(red: number, green: number, blue: number, alpha: number = 255) {
        this.R = red;
        this.G = green;
        this.B = blue;
        this.A = …

我想data-index在其(嵌套)子节点之一上设置父元素的值.期望的结果:字符串"index"应该出现在h2.heading.

标记:

<div class="foo" data-index="index">
    <div>
        <h2 class="heading"><span>title</span></h2>
    </div>
</div>

CSS(第一条data-index规则有效 - 但不是在正确的地方):

div.foo[data-index] .heading span {
    display: none;
}

div.foo[data-index]::after { 
    content: attr(data-index);
    color: green;
}

div.foo[data-index] .heading::after { 
    content: attr(data-index);
    color: red;
    border: 1px solid red;
}

http://codepen.io/anon/pen/jyxdoz

我尝试在我的index.js.

完整错误：

class Clear extends Moderation {
                    ^
TypeError: Class extends value undefined is not a constructor or null
    at Object.<anonymous> (C:\Users\Chigu\SoftKr\Asuha-Discord-Universal-Bot\Src\Actions\Moderation\Commands\Clear.js:5:21)
    at Module._compile (internal/modules/cjs/loader.js:1133:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)
    at Module.load (internal/modules/cjs/loader.js:977:32)
    at Function.Module._load (internal/modules/cjs/loader.js:877:14)
    at Module.require (internal/modules/cjs/loader.js:1019:19)
    at require (internal/modules/cjs/helpers.js:77:18)
    at Object.<anonymous> (C:\Users\Chigu\SoftKr\Asuha-Discord-Universal-Bot\Src\Actions\Moderation\Moderation.js:2:17)
    at Module._compile (internal/modules/cjs/loader.js:1133:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)

Process finished with exit code 1

清除.js

const Discord = require("discord.js");
const {Moderation} = require("../Moderation");

class Clear extends Moderation {
    constructor(message, client) {
        super(message, client);
        this.command = "clear";
   } …