JavaScript regex not replacing '@' character

Question

I am new to JavaScipt and testing a regular Expression and is working on below use case -

Requirement - Replace every character with '#' that is NOT FROM BELOW LIST-

Number
Character (upper or lower case)
Any special character except -> comma, dot, square brackets, forward slash, single Quote

Please find my code below -

    var replacedStr = str.replace(/[^a-zA-Z0-9'.-\[\], ]/g,"#");

Output for various values of str are -

   str = "hello_";
   replacedStr is hello#
   _______________________
   str = "hello@_";
   replacedStr is hello@#

I wanted to know why '@' isnot being replaced from above regex.

The same behavior is with characters - underScore, question-Mark, Angular brackets.

Please guide.

Thanks,

Vibhav

As it does in A-Z, the dash in .-[ is creating a range of characters — John Hascall
– John Hascall, Commented Jun 2, 2017 at 5:50

Tim Biegeleisen · Accepted Answer · 2017-06-02 05:55:02Z

2

In your original regex, your dash (hyphen) is being interpreted as a range:

[^a-zA-Z0-9'.-\[\], ]

This is being intepreted as the range of characters from dot . until opening bracket [, which includes the at symbol. If you move the hyphen to the very end of the negated character class, the regex will work as intended:

str = "hello@_";
str = str.replace(/[^a-zA-Z0-9'.\[\], -]/g,"#");
console.log(str);

edited Jun 2, 2017 at 5:55

answered Jun 2, 2017 at 5:49

Tim Biegeleisen

526k32 gold badges324 silver badges399 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Manish Madugula · Accepted Answer · 2017-06-02 05:59:56Z

0

Couple of mistakes in your reg-ex you have to put '-' in front of charachter class (or at last).

Below reg-ex will do the trick

/[^.,\[\]\\'a-zA-Z0-9]/g

you can use online testers like http://www.regexpal.com/ to check regex's

answered Jun 2, 2017 at 5:59

Manish Madugula

1491 silver badge9 bronze badges

Comments

selvakumar · Accepted Answer · 2017-06-02 06:01:37Z

0

Hyphen will be taken as a range, hence you need to add a escape sequence to it.

str.replace(/[^a-zA-Z0-9'.\-\[\]]/g,"#");

answered Jun 2, 2017 at 6:01

selvakumar

6547 silver badges16 bronze badges

Collectives™ on Stack Overflow

JavaScript regex not replacing '@' character

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related