5_扩展运算符.html 952 B

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="UTF-8">
  5. <meta http-equiv="X-UA-Compatible" content="IE=edge">
  6. <meta name="viewport" content="width=device-width, initial-scale=1.0">
  7. <title>Document</title>
  8. </head>
  9. <body>
  10. <ul>
  11. <li>1</li>
  12. <li>2</li>
  13. <li>3</li>
  14. </ul>
  15. <script>
  16. /* ...扩展运算符 把数组或者类数组展开成用逗号分隔开的值 */
  17. // var a = [1,2,3]
  18. // var b = [...a]
  19. // b[0] = 8
  20. // console.log(b)
  21. // console.log(a)
  22. // var c = [1,2,3]
  23. // var d = c
  24. // d[0] = 9
  25. // console.log(c,d)
  26. // var e = [1,2,3]
  27. // console.log(...e)
  28. //合并
  29. var a = [1,2,3]
  30. var b = [4,5,6]
  31. var e = [...a,...b,7,8,9]
  32. console.log(e)
  33. var aLi = document.getElementsByTagName('li')
  34. console.log(aLi)
  35. /* ... 把类数组转数组 */
  36. var arr = [...aLi]
  37. console.log(arr)
  38. arr.push(11)
  39. console.log(arr)
  40. </script>
  41. </body>
  42. </html>