35 lines
385 B
Markdown
35 lines
385 B
Markdown
# 作用域
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```javascript
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var color = "blue";
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function changeColor(){
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if (color === "blue"){
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color = "red";
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} else {
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color = "blue";
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}
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}
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changeColor();
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alert("Color is now " + color);
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```
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## 特殊情况
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- if
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- for
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- ...
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> 垃圾回收 gc
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## 执行上下文
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> 内侧函数可以调用父级作用域的变量
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## 垃圾清除
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- 标记清除
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- 引用计数
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