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HTML

CSS

CSS Base

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+ add another resource

JavaScript

Babel includes JSX processing.

Add External Scripts/Pens

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+ add another resource

Packages

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Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.

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Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

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Code Indentation

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HTML

              
                <div class="container">
  <div class="preview div"></div>
  <pre class="preview pre"></pre>
  <textarea class="textarea"></textarea>
</div>

              
            
!

CSS

              
                body {
  display:flex;
  margin: 0;
    justify-content: center;
    align-items: center;
    padding: 0 10px;
    box-sizing: border-box;
    min-height: 100vh;
}
.container {
  
    display: flex;
    width: 100%;
}

.div {
  min-width: 220px;
}


.preview {
  flex: 1;
  margin-bottom: 20px;
  padding: 20px;
  background: #f5fcff;
  border: 1px solid #d3eeff;
  border-radius: 3px;
  margin: 0;
}

.textarea {
  flex: 1;
  min-width: 220px;
  margin-left: 20px;
  padding: 10px;
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;
}

.preview + .preview {
  margin-left: 10px;
}
              
            
!

JS

              
                const isPlainObject = (v) => Object.prototype.toString.call(v) === "[object Object]"
const isString = (v) => Object.prototype.toString.call(v) === "[object String]"

/**
 * 格式 JSON 字符串为对象
 *
 * @author anran758
 * @param { any }
 */
function formatJsonStrAsObj(sample) {
  let temp = sample;

  if (isString(temp)) {
    // 因为有解析失败的可能,使用 try catch 做相应处理
    try {
      temp = JSON.parse(temp);
    } catch (ex) {
      // parse error,return this sample
      return sample;
    }
  }

  if (isPlainObject(temp)) {
    temp = { ...temp };

    Object.keys(temp).forEach(key => {
      const item = temp[key];

      // 字符串或者对象进行递归确认
      if (isString(item) || isPlainObject(item)) {
        temp[key] = formatJsonStrAsObj(item);
      }
    });
  }

  return temp;
}

/**
 * 将 JSON 字符串转换为带缩进的字符串
 *
 * @param {*} sample JSON 字符串
 * @param {number} [indnt=2] 缩进数
 * @returns
 */
function formatJSONIndnt(sample, indnt = 2) {
  const newSample = formatJsonStrAsObj(sample);

  if (isString(newSample)) return newSample;

  try {
    return JSON.stringify(newSample, null, indnt);
  } catch (ex) {
    return newSample.toString();
  }
}

const info = JSON.stringify({
  name: 'anran758',
  avatar: 'https://xxx',
  detail: JSON.stringify({
    desc: 'some description',
    level: 2,
  })
})
const data = formatJSONIndnt(info);

const textarea = document.querySelector('.textarea');
const preview = document.querySelector('.pre');
const div = document.querySelector('.div');

textarea.addEventListener('paste', (e) => {
  const value = (e.clipboardData || window.clipboardData).getData('text');
  e.target.value =formatJSONIndnt(value, 2);
  e.preventDefault();
})
preview.innerHTML = data;
div.innerHTML = `
复制下面示例代码到输入框试试<br><br>
${data}`
              
            
!
999px

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