2018-10-10 22:03:03 +00:00
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---
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id: 587d7fad367417b2b2512be1
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2021-03-09 15:51:59 +00:00
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title: 使用 onclick 属性处理点击事件
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2018-10-10 22:03:03 +00:00
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challengeType: 6
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2020-09-07 08:18:38 +00:00
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forumTopicId: 301503
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2021-01-13 02:31:00 +00:00
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dashedName: handle-click-events-with-javascript-using-the-onclick-property
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2018-10-10 22:03:03 +00:00
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---
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2020-12-16 07:37:30 +00:00
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# --description--
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2021-03-09 15:51:59 +00:00
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你希望代码仅在页面完成加载后执行。 为此,你可将名为`DOMContentLoaded`的 JavaScript 事件附加到文档中。 以下是实现的代码:
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2020-09-07 08:18:38 +00:00
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```js
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document.addEventListener('DOMContentLoaded', function() {
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});
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```
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2021-03-09 15:51:59 +00:00
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你可以在`DOMContentLoaded`函数内部添加事件处理方法。 你可以添加`onclick`事件处理器,当用户点击 id 为`getMessage`的元素时会触发事件。 添加以下代码:
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2020-09-07 08:18:38 +00:00
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```js
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document.getElementById('getMessage').onclick = function(){};
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```
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2020-12-16 07:37:30 +00:00
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# --instructions--
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2018-10-10 22:03:03 +00:00
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2021-03-09 15:51:59 +00:00
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在`DOMContentLoaded`函数内为 id 为`getMessage`的元素添加一个 click 事件处理器。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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# --hints--
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2018-10-10 22:03:03 +00:00
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2021-03-09 15:51:59 +00:00
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你的代码应该用`document.getElementById`方法来选择`getMessage`元素。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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```js
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assert(code.match(/document\s*\.getElementById\(\s*?('|")getMessage\1\s*?\)/g));
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2018-10-10 22:03:03 +00:00
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```
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2021-03-09 15:51:59 +00:00
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你的代码应该添加`onclick`事件处理器。
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2018-10-10 22:03:03 +00:00
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2020-12-16 07:37:30 +00:00
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```js
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assert(typeof document.getElementById('getMessage').onclick === 'function');
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2018-10-10 22:03:03 +00:00
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```
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2020-08-13 15:24:35 +00:00
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2021-01-13 02:31:00 +00:00
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# --seed--
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## --seed-contents--
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```html
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<script>
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document.addEventListener('DOMContentLoaded', function(){
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// Add your code below this line
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// Add your code above this line
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});
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</script>
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<style>
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body {
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text-align: center;
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font-family: "Helvetica", sans-serif;
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}
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h1 {
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font-size: 2em;
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font-weight: bold;
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}
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.box {
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border-radius: 5px;
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background-color: #eee;
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padding: 20px 5px;
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}
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button {
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color: white;
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background-color: #4791d0;
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border-radius: 5px;
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border: 1px solid #4791d0;
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padding: 5px 10px 8px 10px;
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}
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button:hover {
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background-color: #0F5897;
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border: 1px solid #0F5897;
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}
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</style>
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<h1>Cat Photo Finder</h1>
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<p class="message box">
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The message will go here
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</p>
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<p>
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<button id="getMessage">
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Get Message
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</button>
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</p>
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```
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2020-12-16 07:37:30 +00:00
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# --solutions--
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2020-09-07 08:18:38 +00:00
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2021-01-13 02:31:00 +00:00
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```html
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<script>
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document.addEventListener('DOMContentLoaded', function(){
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// Add your code below this line
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document.getElementById('getMessage').onclick = function(){ };
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// Add your code above this line
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});
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</script>
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<style>
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body {
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text-align: center;
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font-family: "Helvetica", sans-serif;
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}
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h1 {
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font-size: 2em;
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font-weight: bold;
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}
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.box {
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border-radius: 5px;
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background-color: #eee;
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padding: 20px 5px;
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}
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button {
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color: white;
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background-color: #4791d0;
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border-radius: 5px;
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border: 1px solid #4791d0;
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padding: 5px 10px 8px 10px;
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}
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button:hover {
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background-color: #0F5897;
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border: 1px solid #0F5897;
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}
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</style>
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<h1>Cat Photo Finder</h1>
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<p class="message box">
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The message will go here
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</p>
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<p>
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<button id="getMessage">
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Get Message
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</button>
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</p>
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```
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