Question 293976 in Javascript Question posted in
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Javascript – regex check for global group validation (js)

hi i need to check the validity of all groups and the mixed possibility of creating a world.

for example:

asd
a s d
4 s   d
444ssddd
aaaaa444ssss dddd

must all match.
while:

aesd
zxaxvd

anything that have not that pattern

i’ve try with something like this:

(a*|4*|4* *|a* *)(s*|s* *)(d*|d* *)

but this always return true, while should match the entire pattern group:

const regex = '(a*|4*|4* *|a* *)(s*|s* *)(d*|d* *)';
const re = new RegExp(regex, "gi");
const deleteMessage = re.test(text);
Tags:

3

Answers


  1. 0

    The following should work:

    const words=`asd
a s d
 a a 4  as      dd    d  
4 s   d
444ssddd
aaaaa444ssss dddd
aesd
zxaxvd
aa a s4s    d d`.split("n");

words.forEach(w=>console.log(w,w.match(/^ *[a4][a4 ]*s[s ]*d[d ]*$/)));

    In your regexp you used the * quantifier which also allows zero occurrences, while in my pattern I require at least one occurrence of the letters a or 4, s and d.

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  2. 0

    Your pattern has no bounds and doesn’t actually require anything because it uses asterisks for everything, so even an empty string is valid. This should do the trick by adding start and end bounds as well as requiring at least one character from each grouping.

    ^([a4]+ *)(s+ *)(d+ *)$
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  3. 0

    There are two issues with your regex:

    1. everything is optional, so it will match an empty string;
    2. because you don’t have any anchors on your regex, it will thus match every input (since all strings have empty strings in them).

    You can fix that by using this regex:

    ^(?:a*4+|a+4*) *s+ *d+ *$

    which matches:

    • ^ : beginning of string
    • (?:a*4+|a+4*) : 0 or more a followed by 1 or more 4; or 1 or more a followed by 0 or more 4
    • * : some number of spaces
    • s+ : 1 or more s
    • * : some number of spaces
    • d+ : 1 or more d
    • * : some number of spaces
    • $ : end of string

    Regex demo on regex101

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