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js变量作用域

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Release： 2016-06-01 09:55:05
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当在函数内部定义变量时，一定要用var定义，否则该变量将是全局变量。

实例：

<code>function fn1{    
   b=2;
   alert(b);
}</code>
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此时，如果页面执行了fn1函数，则b变量将成为全局变量。

 

Related labels：
Scope variable
source：php.cn
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