forEach
    对数组执行遍历

    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.         var arr = [2,3,4,5];
    11.         // forEach
    12.         /* 
    13.         1.对数组执行遍历
    14.          */
    15.         arr.forEach((item,index)=>{
    16.             console.log(item+"--"+index)
    17.             item+=2;
    19.         })
    20.     </script>
    21. </body>
    22. </html>

    1.PNG