1、手机号中间四位星号展示
var phone = '15188889999'
phone = phone.replace(/^(\d{3})\d{4}(\d+)/,"$1****$2")
console.log(phone)
2、身份证号中间星号展示
var str = '120999199901018789'
str = str.replace(/^(.{6})(?:\d+)(.{3})$/,"$1******$2")
console.log(str)
3、判断手机号是否符合规范
var mobile = '15199990000'
if (!/^(1[3456789])[0-9]{9}$/.test(mobile)) {
alert('请输入正确的手机号')
return
}