push向后添加
    unshift向前添加

    1. <!DOCTYPE html>
    2. <html lang="en">
    3. <head>
    4.     <meta charset="UTF-8">
    5.     <meta name="viewport" content="width=device-width, initial-scale=1.0">
    6.     <title>Document</title>
    7. </head>
    8. <body>
    9.     <script>
    10.         // push向后添加
    11.         // unshift向前添加
    12.         var arr = [1,2,3,4];
    13.         arr.unshift(0);
    14.         console.log(arr);
    15.     </script>
    16. </body>
    17. </html>

    1.PNG