JS通过身份证号获取出生年月日的方法：

VUE中适用的方法：

 handleIdCard(val) {
      // this.rowData.dateOfBirth = this.getBirthdayFromIdCard(val)
      if (val) {
        this.rowData.dateOfBirth = dateFormat(this.getBirthdayFromIdCard(val), 'yyyy-MM-dd hh:mm:ss')
      } else {
        this.rowData.dateOfBirth = ''
      }
    },
    getBirthdayFromIdCard(idCard) {
      let birthday = ''
      if (idCard !== null && idCard !== '' && idCard.length === 18) {
        birthday = idCard.substr(6, 8)
        birthday = birthday.replace(/(.{4})(.{2})/, '$1-$2-')
      }
      return birthday
    }