Regex to check only capital letters, two special characters (& and Ñ) & without any space between

Question

I am using below code snippet to validate my input string with: only capital letters, numbers and two special characters (those are & and Ñ) & without any space between.

var validpattern = new RegExp('[^A-Z0-9\d&Ñ]');
if (enteredID.match(validpattern))
   isvalidChars = true;
else
   isvalidChars = false;

Test 1: "XAXX0101%&&$#" should fail i.e isvalidChars = false; (as it contains invalid characters like %$#.

Test 2: "XAXX0101&Ñ3Ñ&" should pass.

Test 3: "XA 87B" should fail as it contains space in between

The above code is not working, Can any one help me rectifying the above regex.

Solution 1

This is happening because you have a negation(^) inside the character class.

What you want is: ^[A-Z0-9&Ñ]+$ or ^[A-Z\d&Ñ]+$

Changes made:

• [0-9] is same as \d. So use either of them, not both, although it's not incorrect to use both, it's redundant.
• Added start anchor (^) and end anchor($) to match the entire string not part of it.
• Added a quantifier +, as the character class matches a single character.

Solution 2

^[A-Z\d&Ñ]+$

0-9 not required.

Solution 3

if you want valid patterns, then you should remove the ^ in the character range.

[A-Z0-9\d&Ñ]

Comments

[Gumbo]

What about your previous question?

[Ikaso]

Maybe you should remove the negation ^.

[Biki]

Thanks for the explanation, but let me know which part of the regex is responsible for checking the spaces?

[codaddict]

@Biki: We are allowing only upper case letters, digits and the two special char. So this automatically does not allow any other characters like the space.

[Biki]

Ya, Very true. Using jquery we could achieve the same in one line: $('#txtFederalTaxId').alphanumeric({ allow: " &Ñ" });

[Simon Dell]

This "in one line" thing isn't a useful metric of "good code". Often a higher count of shorter lines gives your readers better understanding of your intent (and more scope to refactor later). However... if you want a "pure JS" one-liner, try something based on: isvalidChars = /^[A-Z0-9&Ñ]+$/.test(enteredID). This works because JS supports RegEx literals.