使正则表达式不匹配空字符串? [英] Make regular expression not match empty string?

问题描述

我的正则表达式在我的应用程序中运行良好，但它也匹配空字符串，即当输入为空时不会发生错误.如何修改此正则表达式，使其不匹配空字符串?请注意，我不想更改此正则表达式的任何其他功能.

I have regex which works fine in my application, but it matches an empty string too, i.e. no error occurs when the input is empty. How do I modify this regex so that it will not match an empty string ? Note that I DON'T want to change any other functionality of this regex.

这是我使用的正则表达式:^([0-9\(\)\/\+ \-]*)$

This is the regex which I'm using: ^([0-9\(\)\/\+ \-]*)$

我自己对正则表达式的了解并不多，这就是我问的原因.我一直在寻找答案，但找不到直接的答案.我最接近的是:正则表达式除了 c# 中的空字符串 之外的任何东西，但这对我来说真的不起作用..

I don't know a lot about regex formulation myself, which is why I'm asking. I have searched for an answer, but couldn't find a direct one. Closest I got to was this: regular expression for anything but an empty string in c#, but that doesn't really work for me ..

推荐答案

将*"替换为+"，因为*"表示0次或多次出现"，而+"表示至少出现一次"

Replace "*" with "+", as "*" means "0 or more occurrences", while "+" means "at least one occurrence"

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