140 lines
2.8 KiB
Markdown
140 lines
2.8 KiB
Markdown
---
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id: 587d7fad367417b2b2512be1
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title: Handle Click Events with JavaScript using the onclick property
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challengeType: 6
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forumTopicId: 301503
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---
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# --description--
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You want your code to execute only once your page has finished loading. For that purpose, you can attach a JavaScript event to the document called `DOMContentLoaded`. Here's the code that does this:
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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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You can implement event handlers that go inside of the `DOMContentLoaded` function. You can implement an `onclick` event handler which triggers when the user clicks on the element with id `getMessage`, by adding the following code:
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```js
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document.getElementById('getMessage').onclick = function(){};
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```
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# --instructions--
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Add a click event handler inside of the `DOMContentLoaded` function for the element with id of `getMessage`.
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# --hints--
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Your code should use the `document.getElementById` method to select the `getMessage` element.
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```js
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assert(code.match(/document\s*\.getElementById\(\s*?('|")getMessage\1\s*?\)/g));
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```
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Your code should add an `onclick` event handler.
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```js
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assert(typeof document.getElementById('getMessage').onclick === 'function');
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```
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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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# --solutions--
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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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