JavaScript: match a word in a text with a word in array and replace it-CodePudding

I need to change this text:

var text = `this is an example text. 1coffee , 2 coffee , 1 apple, 2apple , ?banana ,carrot`;

using these 2 arrays :

var arrOld = ["coffee", "apple", "banana" , "carrot"];
var arrnew = ["laptop", "keyboard", "mouse", "printer"];

to get result like this:

`this is an example text. 1laptop , 2 laptop , 1 keyboard, 2keyboard , ?mouse ,printer`

I was trying something like:

for (let i = 0; i < arrOld.length; i  ) {
arrNew[i];
arrOld[i];
text.replace(arrOld[i],arrNew[i])
}

but it didn't work.

CodePudding user response：

You can try this. Modified from your code.

const oldArray = ["coffee", "apple", "banana" , "carrot"];
const newArray = ["laptop", "keyboard", "mouse", "printer"];

let text = `this is an example text. 1coffee , 2 coffee , 1 apple, 2apple , ?banana ,carrot`;

const { length } = oldArray
for (let i = 0; i < length; i  ) {
  text = text.replace(oldArray[i], newArray[i]);
}

console.log(text);

CodePudding user response：

From the docs on .replace (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replace):
"The replace() method returns a new string with some or all matches of a pattern replaced by a replacement."
This means that text.replace() doesn't manipulate the text variable. To fix this, simply do the following in your loop:
text = text.replace()
This will catch the changed text into the text variable. Without doing this, you are making the changes, but you are not using them (you forget them).

CodePudding user response：

replace returns a new string instead of changing the old one

you can use reduce

also add RegExp because replace works only for the first match it found

const text = `this is an example text. 1coffee , 2 coffee , 1 apple, 2apple , ?banana, another banana ,carrot`;

var arrOld = ["coffee", "apple", "banana" , "carrot"];
var arrnew = ["laptop", "keyboard", "mouse", "printer"];

const resultWitoutRegexp =  arrOld.reduce((res, textToChange, i) => res.replace(textToChange, arrnew[i]) , text)

const result = arrOld.reduce((res, textToChange, i) => res.replace(new RegExp(textToChange, 'g'), arrnew[i]) , text)
console.log(resultWitoutRegexp)
console.log(result)

CodePudding user response：

You could use String.prototype.replaceAll():

var text = "this is an example text. 1coffee , 2 coffee , 1 apple, 2apple , ?banana ,carrot";
var arrOld = ["coffee", "apple", "banana", "carrot"];
var arrnew = ["laptop", "keyboard", "mouse", "printer"]
for (let i = 0; i < arrOld.length; i  ) {
    text = text.replaceAll(arrOld[i], arrnew[i]);
}
console.log(text);

And maybe also Array.prototype.map():

var text = "this is an example text. 1coffee , 2 coffee , 1 apple, 2apple , ?banana ,carrot";
var arrOld = ["coffee", "apple", "banana", "carrot"];
var arrnew = ["laptop", "keyboard", "mouse", "printer"];
arrOld.map((old, i) => text = text.replaceAll(old, arrnew[i]));
console.log(text);