1. //在字符串中查找是否有符合条件的
    2. console.log(/[a-zA-Z]+/.test("hello"));
    3. console.log(/./.test("除了回车换行以为的任意字符"));//true
    4. console.log(/.*/.test("0个到多个"));//true
    5. console.log(/.+/.test("1个到多个"));//true
    6. console.log(/.?/.test("哈哈"));//true
    7. console.log(/[a-z]/.test("what"));//true
    8. console.log(/[A-Z]/.test("Are"));//true
    9. console.log(/[a-zA-Z]/.test("干啥子"));//false
    10. console.log(/[0-9a-zA-Z]/.test("9ebg"));//true
    11. console.log(/b|(ara)/.test("abra"));//true
    12. console.log(/[a-z]{2,3}/.test("arfsf"));//true
    13. console.log(/\d/.test("998"));//true
    14. console.log(/\d*/.test("998"));//true
    15. console.log(/\d+/.test("998"));//true
    16. console.log(/\d{0,}/.test("998"));//true
    17. console.log(/\d{2,3}/.test("998"));//true
    18. console.log(/\D/.test("eat"));//true
    19. console.log(/\s/.test(" "));//true
    20. console.log(/\S/.test("嘎嘎"));//true
    21. console.log(/\w/.test("_"));//true
    22. console.log(/\W/.test("_"));//fasle