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JS??? ?? ???? "??"???.

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<!DOCTYPE HTML>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
        <title>php.cn</title>
        <script>
            var arr = ["濤哥" , "男" , 24, "大專" , "北京科技大學" ];
                document.write(arr.length);
        </script>
    </head>
    <body>
    </body>
</html>

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<!DOCTYPE HTML>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
        <title>php.cn</title>
        <script>          
            //使用[]方式創(chuàng)建一個數(shù)組
            var arr = [
                [1,2,3,4],
                [4,5,6,7],
                [8,9,10,11]
            ];         
            document.write(arr);        
        </script>
    </head>
    <body>
    </body>
</html>

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  • 2?? ??? ?? ???: ?? ?? ??? ?? ?? ??? ??? []? ??, ? ?? ??? []? 1?? ??? ????, ? ?? ??? []? 2?? ??.

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||
<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>php.cn</title> <script> var arr = ["濤哥" , "男" , 24, "大專" , "北京科技大學" ]; document.write(arr.length); </script> </head> <body> </body> </html>