Javascript find all occurances substring in string

 

const str = "JavaScript is awesome. JavaScript is popular.";

const sub = "JavaScript";

let index = str.indexOf(sub);

while (index !== -1) {

    console.log(index);

    index = str.indexOf(sub, index + 1);

}

Output:

0

23

Explanation:

1. The `indexOf` method is used to find the first occurrence of the substring "JavaScript" in the string `str`.

It returns the index of the first occurrence, which is 0.

2. The `while` loop continues to search for the substring "JavaScript" starting from the index after the last

found occurrence (index + 1). The next occurrence is found at index 23.

3. The loop continues until `indexOf` returns -1, indicating that there are no more occurrences of the

substring in the string. The final output is the indices of the occurrences of "JavaScript" in the string,

which are 0 and 23.