2025-3-4-javaScript-变量 


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    <meta charset="UTF-8">
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    <title>Document</title>
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    <script>
        //  变量提升，会将变量声明提前，赋值不变，打印出来undefined
        console.log(a);
        // var-声明 a-变量名 10-值
        var a = 10;
        // 打印出来10
        console.log(a);
    </script>
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</html>
posted @ 2025-03-04 21:50  liu某人  阅读(18)  评论(0)    收藏  举报