13.Map.html 1.5 KB

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  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. // Map对象
  11. let s1 = new Map();
  12. console.log(s1);
  13. // 设置
  14. s1.set("name","孙悟空");
  15. s1.set("age",18);
  16. console.log(s1);
  17. // 获取
  18. console.log(s1.get("name"));
  19. // 删除
  20. // console.log(s1.delete("name"));
  21. // s1.delete("name")
  22. // size 获取当前map对象长度
  23. // console.log(s1.size);
  24. // clear 清空全部
  25. s1.clear();
  26. console.log(s1);
  27. // 数据循环 对已有数组进行操作
  28. var arr = [12,21,23,45,32,3];
  29. arr.map((ele,index) => {
  30. console.log(ele,index);
  31. })
  32. var s2 = new Map();
  33. s2.set("name","猪八戒");
  34. s2.set("age",22);
  35. console.log(s2);
  36. // key 每一项键值对
  37. for (var key of s2) {
  38. console.log(key,'s2')
  39. }
  40. // keys() 每一项可枚举属性名
  41. for(var a of s2.keys()) {
  42. console.log(a,'keys');
  43. }
  44. // values() 每一项可枚举属性值
  45. for(var a of s2.values()) {
  46. console.log(a,'values');
  47. }
  48. // entries() 每一项可枚举的键值对
  49. for(var a of s2.entries()) {
  50. console.log(a,'entries');
  51. }
  52. </script>
  53. </body>
  54. </html>