2018-01-26 15:18:56 +08:00
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JS的小知识.md
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### 方法的注释
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2018-02-01 22:58:37 +08:00
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方法写完之后（注意，一定要先写完整），我们在方法的前面输入`/**`，然后回车，会发现，注释的格式会自动补齐。
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比如：
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```javascript
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/**
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* 功能：给定元素查找他的第一个元素子节点，并返回
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* @param ele
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* @returns {Element|*|Node}
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*/
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function getFirstNode(ele){
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var node = ele.firstElementChild || ele.firstChild;
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return node;
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}
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```
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2018-01-26 15:18:56 +08:00
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### 断点调试
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（1）先让程序运行一遍。
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（2）f12，弹出代码调试工具
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（3）打断点：
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然后刷新页面。
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（4）一步步调试，每点击一次，执行一步：
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（5）监视变量：
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当然，也可以添加变量或者表达式到监视窗口。操作如下：
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上图中，选择变量或表达式，然后右键add to watch.
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然后监视窗口：
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