正则 - 掘金

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         <title>Document</title>
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        <script>
 
    


    // let reg = /^张/i
    // let str = '张飞'
    // console.log(reg.test(str));
    
    // let reg = /^[186]{6}$/i
    // let str = '45678'
    // console.log(reg.test(str));


    // let reg = /^(18|16|26){6}$/i
    // let str = '['
    // console.log(reg.test(str));
    
    // let reg = /^(\.|\[|\]|{|\}|\|)$/i
    // let str = '['
    // console.log(reg.test(str));
    // let reg = /^[a-zA-z]{1,5}$/i
    // let reg = /^[a-zA-z]{1,5}$/i

    
    

     let reg = /^\w{0,20}@\w{0,10}\.(com|net|cn|org)$/
    let str = 'zz@qq.com'
      console.log(reg.test(str));
    
    
    
</script>
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    </html>