Count special characters in a string

Question

i have the following piece of code to count number of special characters in a string...somehow it does not return what i'd like

var sectionToCheck  = $('input').val(); //it could be any kind of string entered in an input field such as "Hello @&% everybody"
var specialChars = /^[!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]*$/;
var allFoundCharacters = sectionToCheck.match(specialChars);
console.log(allFoundCharacters);

It returns a null value for the variable allFoundCharacters. Any tips please?

possible duplicate of [Count the number of occurences of a character in a string in Javascript](http://stackoverflow.com/questions/881085/count-the-number-of-occurences-of-a-character-in-a-string-in-javascript) — Tobias Golbs, Aug 24 '15 at 12:48
also, do you want to count the chars, strip them, want a string without special chars returned? — Alex, Aug 24 '15 at 12:49
What are NOT special characters? `a-z` and `0-9` in your case? — lshettyl, Aug 24 '15 at 13:00

score 6 · Accepted Answer · answered Aug 24 '15 at 12:48

6

You've included ^ which matches the start of the string, and $ for the end. Your regex will only match strings comprised entirely of special characters.

answered Aug 24 '15 at 12:48

cjol

1,485
11
26

3

for the sake of completeness: `var specialChars = /[!@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]/gi; ` – Alex Aug 24 '15 at 12:53

score 3 · Answer 2 · edited Aug 24 '15 at 13:46

3

Try this. Hope it will help you.

var str= "This is a string.";

// the g in the regular expression says to search the whole string rather than just find the first occurrence

var count = (str.match(/is/g) || []).length;

alert(count);

edited Aug 24 '15 at 13:46

Raghavendra

3,530
1
17
18

answered Aug 24 '15 at 13:22

Rahul_Vijay

39
3

score 1 · Answer 3 · answered Aug 24 '15 at 12:54

1

Try this:

/[@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]/g

Full code:

var sectionToCheck  = "$%klds$"; 
var allFoundCharacters = sectionToCheck.match(/[@#$%^&*()_+\-=\[\]{};':"\\|,.<>\/?]/g);
alert(allFoundCharacters.length);//count

answered Aug 24 '15 at 12:54

Manwal

23,450
12
63
93

Count special characters in a string

3 Answers3