JavaScript: Count the occurrence of a substring in a string
JavaScript String: Exercise-18 with Solution
Write a JavaScript function to count the occurrence of a substring in a string.
Test Data:
console.log(count("The quick brown fox jumps over the lazy dog", 'the'));
Output:
2
console.log(count("The quick brown fox jumps over the lazy dog", 'fox',false));
Output:
1
Pictorial Presentation:

Sample Solution:-
HTML Code:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Write a JavaScript function to count the occurrence of a substring in a string.</title>
</head>
<body>
</body>
</html>
JavaScript Code:
function count(main_str, sub_str)
{
main_str += '';
sub_str += '';
if (sub_str.length <= 0)
{
return main_str.length + 1;
}
subStr = sub_str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
return (main_str.match(new RegExp(subStr, 'gi')) || []).length;
}
console.log(count("The quick brown fox jumps over the lazy dog", 'the'));
console.log(count("The quick brown fox jumps over the lazy dog", 'fox',false));
Sample Output:
2 1
Flowchart:

Live Demo:
See the Pen JavaScript Count the occurrence of a substring in a string - string-ex-18 by w3resource (@w3resource) on CodePen.
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