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const reg = /^([a-z0-9_\.-]+)@([\da-z\.-]+)\.([a-z\.]{2,6})$/; //正则校验邮箱
if (reg.test(value) || value === ‘‘ || value === ‘-‘) {
}else{
//页面上显示格式不正确
}
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const reg = /^(?=^.{3,255}$)(http(s)?:\/\/)?(www\.)?[a-zA-Z0-9][-a-zA-Z0-9]{0,100}(\.[a-zA-Z0-9][-a-zA-Z0-9]{0,100})+(:\d+)*(\/\w+\.\w+)*$/ //正则校验域名
const reg = /^[0-9]{2,18}$/; //正则校验供外部端口
const reg = /^-?(0|[1-9][0-9]*)(\.[0-9]*)?$/; //正则校验实例数
