Please can someone assist me with a regular expression to validate a string of this pattern
aaa [bbb]
I want to an input in the format expressed above. aaa & bbb can be any combination of one or more words which could also contain special characters. bbb must be contained inside square brackets ([...]). The full string can have a leading or trailing spaces.
I have tried this:
var re=/\w{0,} \[*\w{0,}\]/
But it returns false on a test string like:
re.test("onc>*!llklk[dd<dfd]")
Your regular expression explicitly requires a space to be present. We can visualise this with Regexper:
This returns false on "onc>*!llklk[dd<dfd]" because there is no space character.
To fix your problem, either use a test string which has a space character, or change your regular expression to not require this character:
var re = /\w{0,}\[*\w{0,}\]/;
re.test("aaa [bbb]");
> true
re.test("onc>*!llklk[dd<dfd]");
> true
You may want to rethink your regular expression though, because as it stands, a single "]" character will pass the test:
re.test("]");
> true
\S+\s*\[\S+?\]
You can try this if you want to allow special characters as well.
First, to make it easier to read, you could replace {0,} by * as it's the same thing.
Next, \w would not match some symbols like > or *, you can use a . to match any symbol.
Then, like an other answer is saying, you're expecting a space between the two groups (aaa and [bbb]), so your example won't match.
I think this regex is a good starting point (depending on your other requirements).
/.+\[.+\]/
* by a +. I edited. If you need at least one character between the [] too, you should replace the second * too.