2018-10-10 18:03:03 -04:00
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---
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id: 587d7fae367417b2b2512be6
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2020-12-16 00:37:30 -07:00
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title: 渲染数据源的图像
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2018-10-10 18:03:03 -04:00
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challengeType: 6
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2020-09-07 16:18:38 +08:00
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forumTopicId: 18265
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2021-01-13 03:31:00 +01:00
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dashedName: render-images-from-data-sources
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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前几个挑战中表明,JSON 数组中的每个对象都包含一个`imageLink`键,其值为猫图像的 URL。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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当你遍历这些对象的时候,你可以使用`imageLink`属性在`img`元素中显示此图像。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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这是执行此操作的代码:
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`html += "<img src = '" + val.imageLink + "' " + "alt='" + val.altText + "'>";`
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --instructions--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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添加代码以在`img`标签中使用`imageLink`和`altText`属性。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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你应该使用`imageLink`属性来显示图像。
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2020-09-07 16:18:38 +08:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(code.match(/val\.imageLink/g));
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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应该用 `altText` 做为图片的 alt 属性。
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2020-09-07 16:18:38 +08:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(code.match(/val\.altText/g));
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2018-10-10 18:03:03 -04:00
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```
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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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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document.getElementById('getMessage').onclick = function(){
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const req=new XMLHttpRequest();
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req.open("GET",'/json/cats.json',true);
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req.send();
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req.onload = function(){
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const json = JSON.parse(req.responseText);
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let html = "";
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json.forEach(function(val) {
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html += "<div class = 'cat'>";
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// Add your code below this line
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// Add your code above this line
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html += "</div><br>";
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});
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document.getElementsByClassName('message')[0].innerHTML=html;
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};
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};
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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 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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```html
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<script>
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document.addEventListener('DOMContentLoaded', function(){
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document.getElementById('getMessage').onclick = function(){
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const req = new XMLHttpRequest();
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req.open("GET",'/json/cats.json',true);
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req.send();
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req.onload = function(){
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const json = JSON.parse(req.responseText);
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let html = "";
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json.forEach(function(val) {
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html += "<div class = 'cat'>";
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// Add your code below this line
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html += "<img src = '" + val.imageLink + "' " + "alt='" + val.altText + "'>";
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// Add your code above this line
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html += "</div><br>";
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});
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document.getElementsByClassName('message')[0].innerHTML = html;
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};
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};
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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">
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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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