正则表达式:匹配两个条件之一? [英] Regular expression : match either of two conditions?

问题描述

我对正则表达式了解不多.但是我需要使用angularJs进行表单验证.

Hi I don't know much about regular expression. But I need it in form validation using angularJs.

以下是要求

输入框应仅在以下任一情况下接受

The input box should accept only if either

(1)前2个字母的字母+ 6个数字

或

(2)8位数字

下面是一些正确的输入:-

Below are some correct Inputs :-

(1)SH123456(2)12345678(3)sd456565

(1)SH123456 (2)12345678 (3)sd456565

我尝试了 data-ng-pattern ="/(^([a-zA-Z]){2}([0-9]){6})|([0-9] *)?$/"，在上述条件下都可以正常工作，但仍可以接受S2D3E4F5之类的字符串，并且可能还有许多其他组合.

I tried data-ng-pattern="/(^([a-zA-Z]){2}([0-9]){6})|([0-9]*)?$/" , Its working fine for both the above condition but still it is accepting strings like S2D3E4F5 and may be many other combination as well.

我做错了什么，我找不到它.

What I am doing wrong I am not able to find it out.

任何帮助都是有意义的！

Any help is appreciable !!!

谢谢

推荐答案

在您的正则表达式中，两个替代分支分别锚定:

In your regex, the two alternative branches are anchored separately:

• (^([a-zA-Z]){2}([0-9]){6})-字符串开头的2个字母和6个数字
• | -或
• ([0-9] *)?$ -字符串末尾的可选零个或多个数字

• (^([a-zA-Z]){2}([0-9]){6}) - 2 letters and 6 digits at the start of the string
• | - or
• ([0-9]*)?$ - optional zero or more digits at the end of the string

您需要调整组的边界:

data-ng-pattern="/^([a-zA-Z]{2}[0-9]{6}|[0-9]{8})?$/"
                   ^                         ^^^^ 

请参见 regex演示.

现在，模式将匹配:

• ^ -字符串的开头
• (-分组开始:
  • [a-zA-Z] {2} [0-9] {6} -2个字母和6个数字
  • | -或
  • [0-9] {8} -8位数字
  • ^ - start of string
  • ( - start of the grouping:
    • [a-zA-Z]{2}[0-9]{6} - 2 letters and 6 digits
    • | - or
    • [0-9]{8} - 8 digits

    这篇关于正则表达式:匹配两个条件之一?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！