如何编写一个if语句来检查输入是否有字母 [英] How to write an if statement that checks if input has any letters

问题描述

我需要一个正则表达式，当输入中存在字母时，它可以使我成为true.我已经尝试过 if(formula.contains("[a-zA-Z] +")== true)，但这似乎不起作用.

I need a regex that gives me true when a letter exists in the input. I have tried if (formula.contains("[a-zA-Z]+") == true), but this does not seem to work.

嗨！我想到了！ formula.matches(.* [a-zA-Z].*")这行得通！

Hi! I figured it out! formula.matches(".*[a-zA-Z].*") this worked!

推荐答案

为此，您需要 String#matches(regex)和正确的 regex 当然

You'll need String#matches(regex) for this and a correct regex of course

if (formula.matches(".*[a-zA-Z].*")) {
    // do stuff
}

上面的正则表达式表示

.             Any character
 *            Zero or multiple times
  [a-zA-Z]    One letter in ranges a-z or A-Z
          .   Any character
           *  Zero or multiple times

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