Question 190840 in Javascript Question posted in
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Javascript – Replace words with array map, globaly

refering to Replace words with array map
the answer is good, but I would like to add global replace to it.

const arrString = ["beginning=beginner", "leaves=leave", "sound=sounds"];

let string = "its beginner in the sounds leave";

arrString.forEach((mapString) => {
  const stringArr = mapString.split("=");
  string = string.replace(stringArr[1], stringArr[0]);
});

console.log("string", string);

I tried

string.replace(/stringArr[1]/p, stringArr[0]);

Tried it on a string having the same word 3 times.
not working, only the first is replaced.

Tags:

2

Answers


  1. 0

    To perform a global replace using a regular expression in JavaScript, you can use the g flag.

    just modify your code

    const arrString = ["beginning=beginner", "leaves=leave", "sound=sounds"];

let string = "its beginner in the sounds leave";

arrString.forEach((mapString) => {
  const stringArr = mapString.split("=");
  const regex = new RegExp(stringArr[1], "g");
  string = string.replace(regex, stringArr[0]);
});

console.log("string", string);
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  2. 0

    Just use String::replaceAll(), no need in a regular expression here. Also it’s confusing that you have your replacements reversed. Semantically I guess would be better beginner = (means replace beginner with) beginning.

    const arrString = ["beginning=beginner", "leaves=leave", "sound=sounds"];

let string = "its beginner in the sounds leave. beginner again...";

arrString.forEach(mapString => string = string.replaceAll(...mapString.split("=").reverse()));

console.log("string", string);

    If you want regexp anyway:

    const arrString = ["beginning=beginner", "leaves=leave", "sound=sounds"];

let string = "its beginner in the sounds leave. beginner again...";

const replacements = Object.fromEntries(arrString.map(item => item.split('=').reverse()));

string = string.replace(new RegExp(Object.keys(replacements).join('|'), 'g'), m => replacements[m]);

console.log("string", string);

    The regexp version seems a bit faster:

    enter image description here

    <script benchmark data-count="1">

    const arrString = ["beginning=beginner", "leaves=leave", "sound=sounds"];

    let string = "its beginner in the sounds leave. beginner again...".repeat(1000000);

    // @benchmark String::replaceAll()
    {
        let str = string;
        arrString.forEach(mapString => str = str.replaceAll(...mapString.split("=").reverse()));
        str;
    }

    // @benchmark regexp
    {
        const str = string;
        const replacements = Object.fromEntries(arrString.map(item => item.split('=').reverse()));
        str.replace(new RegExp(Object.keys(replacements).join('|'), 'g'), m => replacements[m]);
    }


</script>
<script src="https://cdn.jsdelivr.net/gh/silentmantra/benchmark/loader.js"></script>
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