Using The .replaceAll() on a string literal array in Javascript

Question

Goal: Use an array method to remove the strings get , right , the , first , time and replace them with the single string know in secretMessage array.

Plan Define a function to text in the rain, the old string, and the new string and use to .replaceall() methods and pass each one of the different arguments through one at a time, reassigning the array each call.

Code Thus Far

 let secretMessage = ['Learning', 'is', 'not', 'about', 'what', 'you', 'get', 'easily', 'the', 'first', 'time,', 'it', 'is', 'about', 'what', 'you', 'can', 'figure', 'out.', '-2015,', 'Chris', 'Pine,', 'Learn', 'JavaScript']; function replaceWords(orginalArray,oldString,updatedString){= let updatedArray= orginalArray.replaceAll(oldString,updatedString);//Not Sure If I need to wrap this in [] return updatedArray; } secretMessage = replaceWords(secretMessage,'get','know'); secretMessage = replaceWords(secretMessage,'right','know'); secretMessage = replaceWords(secretMessage,'the','know'); secretMessage = replaceWords(secretMessage,'first','know'); secretMessage = replaceWords(secretMessage,'time','know'); console.log(secretMessage);

Current Results

let updatedArray= orginalArray.replaceAll(oldString,updatedString);
                               ^

TypeError :

orginalArray.replaceAll is not a function at replaceWords

Answer 1

As stated by @Pointy's comment , replaceAll() is a string method, it's not available on an array.

---

So we'll need a way to apply something on each array index .

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Luckily map() does exactly that:

The map() method creates a new array populated with the results of calling a provided function on every element in the calling array .

 let secretMessage = ['Learning', 'is', 'not', 'about', 'what', 'you', 'get', 'easily', 'the', 'first', 'time,', 'it', 'is', 'about', 'what', 'you', 'can', 'figure', 'out.', '-2015,', 'Chris', 'Pine,', 'Learn', 'JavaScript']; function replaceWords(orginalArray,oldString,updatedString){ return orginalArray.map(item => { return item.replaceAll(oldString, updatedString) }); } secretMessage = replaceWords(secretMessage,'get','know'); secretMessage = replaceWords(secretMessage,'right','know'); secretMessage = replaceWords(secretMessage,'the','know'); secretMessage = replaceWords(secretMessage,'first','know'); secretMessage = replaceWords(secretMessage,'time','know'); console.log(secretMessage);

Answer 2

replaceAll is String -function, not an Array -function. If you want to replace a word that maybe exists as value in an array, you have to walk through that array. Your code would look like this:

 let secretMessage = ['Learning', 'is', 'not', 'about', 'what', 'you', 'get', 'easily', 'the', 'first', 'time,', 'it', 'is', 'about', 'what', 'you', 'can', 'figure', 'out.', '-2015,', 'Chris', 'Pine,', 'Learn', 'JavaScript']; function replaceWords(orginalArray,oldString,updatedString){ // because your array-values are just single words, I only use string-comparison, not replaceAll() let updatedArray= orginalArray.map(string => (string == oldString? updatedString: string)); return updatedArray; } secretMessage = replaceWords(secretMessage,'get','know'); secretMessage = replaceWords(secretMessage,'right','know'); secretMessage = replaceWords(secretMessage,'the','know'); secretMessage = replaceWords(secretMessage,'first','know'); secretMessage = replaceWords(secretMessage,'time','know'); console.log(secretMessage);

Answer 3

Just for "fun", a solution using both an array method ( Array.prototype.join() ) and replaceAll() ( String.prototype.replaceAll() ) and close to your original idea, could be:

 function replaceWords(arr, oldStr, newStr) { return arr.join(' ') // join all the array items into a single space-separated string.replaceAll(oldStr, newStr) // call `replaceAll()` on the newly created string.split(' '); // split the string back into an array } let secretMessage = ['Learning', 'is', 'not', 'about', 'what', 'you', 'get', 'easily', 'the', 'first', 'time,', 'it', 'is', 'about', 'what', 'you', 'can', 'figure', 'out.', '-2015,', 'Chris', 'Pine,', 'Learn', 'JavaScript']; secretMessage = replaceWords(secretMessage, 'get', 'know'); secretMessage = replaceWords(secretMessage, 'right', 'know'); secretMessage = replaceWords(secretMessage, 'the', 'know'); secretMessage = replaceWords(secretMessage, 'first', 'know'); secretMessage = replaceWords(secretMessage, 'time', 'know'); console.log(secretMessage);

Having said that, I think nobody would do it in that way in real life;)

Answer 4

You can extend the array functionality to match your requirement. But not recommended.

Just add below code before your array declaration and your code should work.

Array.prototype.replaceAll = function(oldString, updatedString){
    return this.slice().map((str)=>((str === oldString)?updatedString:str));
}

Answer 5

replaceAll() works for strings not arrays. Try the example below.

let secretMessage = ['Learning', 'is', 'not', 'about', 'what', 'you', 'get', 'easily', 'the', 'first', 'time,', 'it', 'is', 'about', 'what', 'you', 'can', 'figure', 'out.', '-2015,', 'Chris', 'Pine,', 'Learn', 'JavaScript'];
    

function replaceWords(orginalArray,oldString,updatedString){=
  let updatedArray= orginalArray.join().replaceAll(oldString,updatedString).split();
  return updatedArray;
}
secretMessage = replaceWords(secretMessage,'get','know');
secretMessage = replaceWords(secretMessage,'right','know');
secretMessage = replaceWords(secretMessage,'the','know');
secretMessage = replaceWords(secretMessage,'first','know');
secretMessage = replaceWords(secretMessage,'time','know');

console.log(secretMessage);