RegEx

buildakicker · 07-29-2009, 12:14 AM

Hi all,

My other post seemed to be a little much?! Maybe this one will be easier...

I am trying to strip an input of any special characters using regExpressions, but am not quite understaning how to get rid of anything but letters and numbers. Isn't there a replace /(!@#%$*())/ all that with "" expression?

Here is what I have so far:

Code:

function updatelink()
{
	var atitle = document.getElementById("articleTitle").value;
	var result = atitle.replace(/(\s| | )+/gi, "-"); //replace spaces
	var clean = result.replace(/'/,""); //replace punctuation
	var postlink = document.getElementById("postlink");
	postlink.firstChild.nodeValue = clean;
	
}

How do I add more than the ' inside the var clean replace?

Thanks!

tony · 07-29-2009, 02:46 AM

This regex could help

Code:

[^A-Za-z0-9]+

it matches anything that is not alphanumeric.
or also the W that matches all alphanumeric, but the W treats the underscore like an alphanumeric. so this

Code:

(/W)+

is the same as

Code:

[^A-Za-z0-9_]+

P.S. I haven't test it.

Salathe · 07-29-2009, 09:57 AM

Quote:

Originally Posted by buildakicker

how to get rid of anything but letters and numbers.

I assume you also want to keep hyphens since they represent where whitespace is in the article title. Here's an amended version of your function, the two regular expressions have been changed to better suit what you're looking for.

JavaScript Code:

function updatelink()
{
    var title = document.getElementById("articleTitle").value;

    // 1. Replace whitespace with hyphen character
    var clean = title.replace(/\s+/g, "-");
    // 2. Strip non-alpnanumeric-or-hyphen characters
    clean = clean.replace(/[^A-Z0-9-]/gi, "");

    var postlink = document.getElementById("postlink");
    postlink.firstChild.nodeValue = clean;
    
}

buildakicker · 07-29-2009, 02:38 PM

Hey Ya! Thanks you guys.

In a string link this:

Code:

var clean = title.replace(/\s+/g, "-");

How do you put this: (/W)+

Like so:

Code:

var clean = title.replace(/(/W)+/g, "-");

? It doesn't like it... Do I need to escape the + ?

Confusing stuff, but essential!

tony · 07-29-2009, 03:24 PM

my bad, it is \W
so something like this would do

javascript Code:

var title = document.getElementById("articleTitle").innerHTML,
    postlink = document.getElementById("postlink"),
    postlinkcontent = postlink.innerHTML,
    clean = title.replace(/\s+/g, "_");
clean = clean.replace(/(\W)/gi, "");
postlink.innerHTML = clean + postlinkcontent;

it is better to use innerHTML than value, I think that is only for form elements, I am not sure.

buildakicker · 07-29-2009, 08:04 PM

Great. I was thinking that \W need the escape. Thanks for the post!

tony · 07-30-2009, 01:30 AM

no problem