JavaScript/jQuery - How to check if a string contain specific words

Question

$a = \'how are you\';
if (strpos($a,\'are\') !== false) {
    echo \'true\';
}

In PHP, we can use the code above to check if a string contain speci

Answer 1

indexOf/includes should not be used for finding whole words:

It does not know the difference between find a word or just a part of a word:

"has a word".indexOf('wor')  // 6
"has a word".includes('wor') // true

---

Check if a single word (whole word) is in the string

Find a real whole word, not just if the letters of that word are somewhere in the string.

const wordInString = (s, word) => new RegExp('\\b' + word + '\\b', 'i').test(s);

// tests
[
  '',            // true
  ' ',           // true
  'did',         // true
  'id',          // flase
  'yo ',         // flase
  'you',         // true
  'you not'      // true
].forEach(q => console.log(
  wordInString('dID You, or did you NOt, gEt WHy?', q) 
))

console.log(
  wordInString('did you, or did you not, get why?', 'you') // true
)

Check if all words are in the string

var stringHasAll = (s, query) => 
  // convert the query to array of "words" & checks EVERY item is contained in the string
  query.split(' ').every(q => new RegExp('\\b' + q + '\\b', 'i').test(s)); 


// tests
[
  '',            // true
  ' ',           // true
  'aa',          // true
  'aa ',         // true
  ' aa',         // true
  'd b',         // false
  'aaa',         // false
  'a b',         // false
  'a a a a a ',  // false
].forEach(q => console.log(
  stringHasAll('aA bB cC dD', q) 
))