CODEWITHSUNDEEP
javascriptregex
Maxim Zhukov
Maxim Zhukov

Reputation: 10140

Regular expression: word between spaces

Sry for stupid question, but there is an example: http://jsfiddle.net/rb98M/

var q = 'SELECT CASE WHEN STATE IN ';
q = q.replace(/(^|\s)\w*(\s|$)/g, function(match) { return match.toLowerCase(); });
alert(q);

I have a string and i want to make lowerCase each word, that's between white spaces (and could be in start of line and end).

But, my result is:

select CASE when STATE in

and that's my problem. Why is it so?

Edit I expect to pass SELECT * FROM [Users] u and get select * from [Users] u and e.t.c (including each SQL statement and exclude any table names and properties in [])

Upvotes: 3

Views: 1907

Answers (2)

Casimir et Hippolyte
Casimir et Hippolyte

Reputation: 89547

You can use this code and put in the capturing group all parts you want to skip:

var q = 'SELECT * FROM [Users] u aNd GeT sElEct * from [Users] U';
q = q.replace(/(\[[^\]]+\])|\w+/g, function(m, g1) {
   return (g1) ? m : m.toLowerCase(); });

The method toLowerCase() is applied to the whole match only if the capturing group is defined.

I used \w to make the pattern shorter, but since it is useless to replace digits, lowercase letters and underscores, you can replace it with [A-Z]

pattern detail:

\[      # a literal [
[^\]]+  # character class with all characters except ] (repeated one or more times)
\]      # a literal ]

Note that you don't need to escape the closing square bracket (or only for very old versions of internet explorer):), you can write: \[[^]]+]

Upvotes: 1

Sabuj Hassan
Sabuj Hassan

Reputation: 39355

Since you are not separating the words with other punctuations. So I believe only using \S is sufficient for you.

q = q.replace(/(\S+)/g, function(match)

In your case it was not working because the \s\w*\s was eating the SELECT(with space at end) from the input and the CASE wasn't have enough space(\s) before it.

Here is how your input was matched using the regex:

SELECT CASE WHEN state IN 
^  m1 ^    ^ m2 ^     ^m3^

Its just ignored the CASE ad the state words from the regex. Because the space before the CASE was picked by the SELECT. You have mandatory space(\s) at the both sides of the word(i.e. \s\w*\s). In other words your regex has overlapping.

Updated regex:

q = q.replace(/(?:\s|^)(\w+)(?=\s|$)/g, function(match)

Upvotes: 3

Related Questions