3.元字符-边界符.html 723 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. // 1.单词边界 \b
  11. const reg = /\ban\b/gi;
  12. const str1 = 'A Cat and An apple';
  13. console.log(str1.match(reg));
  14. // 2.匹配字母首行 ^
  15. const reg1 = /^ab/;
  16. console.log(reg1.test('abaabab'));
  17. const reg2 = /ab$/;
  18. // 3.匹配字母尾行 $
  19. console.log(reg2.test('abaabacb'));
  20. const reg3 = /^a$/;
  21. console.log(reg3.test("aaa"));
  22. console.log(reg3.test("a"));
  23. console.log(reg3.test(" "));
  24. </script>
  25. </body>
  26. </html>