6.分组和分支结构.html 1012 B

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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. // 分组 ()
  11. const reg = /(ab){2}/;
  12. console.log(reg.test("ababababab"));
  13. console.log(reg.test("aaaabb"));
  14. // 分组捕获
  15. // 2024-12-07
  16. const reg1 = /^(\d{4})-(\d{2})-(\d{2})/;
  17. // console.log(reg1.test("2024-12-07"))
  18. // 07/12/2024
  19. // $1 $2 $3
  20. const str = '2024-12-07';
  21. console.log(str.replace(reg1,'$3-$2-$1'))
  22. // 分支结构
  23. const reg3 = /西游记|红楼梦/;
  24. const str1 = '西游记';
  25. const str2 = '水浒传';
  26. const str3 = '红楼梦';
  27. const str4 = '三国演义';
  28. console.log(reg3.test(str1))
  29. console.log(reg3.test(str2))
  30. console.log(reg3.test(str3))
  31. console.log(reg3.test(str4))
  32. </script>
  33. </body>
  34. </html>