RegEx内部的模板文字 [英] Template literal inside of the RegEx

问题描述

我尝试在RegEx中放置模板文字，但它不起作用。然后我创建了一个变量 regex ，它保存了我的RegEx，但它仍然没有给我所需的结果。

I tried to place a template literal inside of a RegEx, and it didn't work. I then made a variable regex which holds my RegEx, but it still not giving me the desired result.

但是如果我单独 console.log（正则表达式），我会收到所需的RegEx，例如 /.+？（？= location）/ i ， /.+？（？= date）/ i 依此类推，但一旦我放置 regex 在 .replace 内，它似乎无法正常工作

However if I console.log(regex) individually, I do receive the desired RegEx, such as /.+?(?=location)/i, /.+?(?=date)/i and so on, but once I place regex inside the .replace it appears not to be working

function validate (data) {
  let testArr = Object.keys(data);
  errorMessages.forEach((elem, i) => {
    const regex = `/.+?(?=${elem.value})/i`;
    const a = testArr[i].replace(regex, '');
    })
  }

推荐答案

您的正则表达式变量是 String 。要使它成为RegExp，请使用

Your regex variable is a String. To make it a RegExp, use

const regex = new RegExp(`.+?(?=${elemvalue.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&')})`, "i"); 

另外，在正则表达式中转义变量部分，因为所有特殊正则表达式元字符都被视为文字。

Also, it is a good idea to escape the variable part in the regex so as all special regex metacharacters were treated as literals.

const s = "final (location)";
const elemvalue = "(location)";
const regex = new RegExp(`.+?(?=${elemvalue.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&')})`, "i");
// console.log(regex); // /.+?(?=\(location\))/i
// console.log(typeof(regex)); // object
let a = s.replace(regex, '');
console.log(a);

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