Regular Expressions + JavaScript

Eoin

Hi folks,

I'm having trouble getting my head around regular expressions. I'm trying to convert all HTML/XML tags to lowercase using JavaScript.

I've gotten as far as this, but can't figure out what I need to replace the question marks with to convert the contents of the tag to lowercase...

var sString = "<B>text</B>";
sString.replace(/<(.|\n)+?>/g, ???);

thanks in advance.

Hobbes

I think the obvious question is .. "Why?". HTML is not case sensitive.

Anyway regexp doesn't work that way. It matches and can replace but you couldn't do a complex replace (that I am aware of).

your expression should be like.

/<[\/ ]*([A-Z]+)[ >]/g

/ = start
< = match literal <
[\/ ]* = Match / or space 0 or unlimited number of times.
([A-Z]+) = Match A to Z any number of times and group into group 1. 
[ >] = Match space or > at least once.
/g = End. (global search).

Should catch most stuff. Won't find the variables in the tag though.

After that do a toLower on the group found and send it back in. Probably an easier way to do this via the DOM though.

Eoin

Hobbes wrote: »

I think the obvious question is .. "Why?". HTML is not case sensitive.

Anyway regexp doesn't work that way. It matches and can replace but you couldn't do a complex replace (that I am aware of).

your expression should be like.

/<[\/ ]*([A-Z]+)[ >]/g

/ = start
< = match literal <
[\/ ]* = Match / or space 0 or unlimited number of times.
([A-Z]+) = Match A to Z any number of times and group into group 1. 
[ >] = Match space or > at least once.
/g = End. (global search).

Should catch most stuff. Won't find the variables in the tag though.

After that do a toLower on the group found and send it back in. Probably an easier way to do this via the DOM though.

Thanks for that. I should have said it was XHTML, which is case sensitive.

I also hope to use this with an XML feed I am working with (the feed elements are in camel case, but the elements I'm matching in our DB are always lowercase and neither can be changed at source).

Hobbes

Ahh ok.. Also check this out.

http://www.codeproject.com/KB/cs/html2xhtmlcleaner.aspx

Eoin

Thanks again Hobbes - it's a bit of a tricky one as the feed I am working off is completely configurable, as are the fields I am trying to match (they are added through a web-based UI). I think a C# component in the middle is the best solution as I can just iterate through the nodes and rename them.

mewso

I think this will do it for you:-

[SIZE=2]mystring = String(mystring).replace(/<(\/?[A-Z][^>]*)>/g, [/SIZE][SIZE=2][COLOR=#0000ff][SIZE=2][COLOR=#0000ff]function [/COLOR][/SIZE][/COLOR][/SIZE][SIZE=2](match) {
[/SIZE][SIZE=2][COLOR=#0000ff][SIZE=2][COLOR=#0000ff]return[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=2] match.toLowerCase();
}
);

[/SIZE]

Eoin

Works a treat, thanks very much!

mewso

Years of dealing with word crap.