Javascript : Detect illegal arrows unicode and replace with blank

Question

Illegal Arrow : escape(strNotes) : result -> "%1A"

This is the illegal Arrow : https://www.htmlsymbols.xyz/unicode/U+001A

I am not able to paste the strNotes but strNotes in system is replaced by an illegal arrow looking character which breaks the system.

Proper Arrow : escape('→') : results -> "%u2192"

But if I use the above proper arrow, it works well.

How to detect the Illegals arrow and special characters in Javascript and remove them from String?

If I try to paste that then after saving it vanishes. I am posting photo of it. — Nagendra Singh, Apr 04 '20 at 07:22
`%1A` is a control character https://en.wikipedia.org/wiki/Substitute_character. You should first figure out how it got there https://stackoverflow.com/questions/17024436 — devio, Apr 04 '20 at 08:02
@devio So the notes were a copy paste from some system. Does that mean there are other characters like this, if so how can we replace them by a `blank`. — Nagendra Singh, Apr 04 '20 at 08:23

score 0 · Answer 1 · answered Apr 04 '20 at 07:19

0

You can use replace(/ /, ''), and replace them all.

answered Apr 04 '20 at 07:19

Nikita

36
5

Use something like this ``` let specialChars = "!@#$^&%*()+=-[]\/{}|:<>?,."; for (let i = 0; i < specialChars.length; i++) { stringToReplace = stringToReplace.replace(new RegExp("\\" + specialChars[i], "gi"), ""); }``` – Nikita Apr 04 '20 at 07:23
This would have worked if I know what I am replacing, but in my case, I dont know that. – Nagendra Singh Apr 04 '20 at 07:24
You can leave only characters str.replace(/[^a-zA-Z ]/g, "") – Nikita Apr 04 '20 at 07:28
@NagendraSingh I thought you said the character was \x1A, so you would write `replace(/\x1A/g, '\u2192')` to replace it with a real arrow. – Mr Lister Apr 05 '20 at 18:08
Yeah actually I ran a loop and included all characters from `https://www.htmlsymbols.xyz/unicode/U+001A` and removed all the characters from `0 - 36` after converting each to unicode. and removed it from the string. – Nagendra Singh Apr 05 '20 at 18:10

score 0 · Answer 2 · answered Apr 04 '20 at 07:33

0

You can replace ASCII characters

text.replace(/[^\ -~]+/g, '')

-~ is minus tilde - ~

answered Apr 04 '20 at 07:33

QuentinUK

2,997
21
20

score 0 · Answer 3 · answered Apr 06 '20 at 04:40

I ended up doing this, thanks to @devio

    String.prototype.toUnicode = function () {
        var uni = [],
            i = this.length;
        while (i--) {
            uni[i] = this.charCodeAt(i);
        }
        return "&#" + uni.join(';&#') + ";";
    };

    let setOfIllegalCharacters = new Set();
    for (let i = 0; i < 32; i++) {
        setOfIllegalCharacters.add("&#" + i + ";");
    }


        // this iterates through the strNotes string and removes all illegal or bad characters.
        for (let i = 0; i < strNotes.length; i++) {
            if (setOfIllegalCharacters.has(strNotes[i].toUnicode())) {
                strNotes = strNotes.replace(strNotes[i], '');
            }
        }

Javascript : Detect illegal arrows unicode and replace with blank

3 Answers3