Question

I have a string of text that I am trying to remove from a textarea in javascript. The text that I am trying to remove is in the following format:

Category:Attribute

Color:Green <- Example!

var catTitle = 'color';
var regexp = new RegExp(catTitle + '\:[.]*$', "g")
textarea.value = textarea.value.replace(regexp, "");

Since the attribute can be any length, I need my regular expression to go forward until the new line. I thought that [.]*$ would be acceptable to match any characters up to a new line; however, it doesn’t seem to work.

Any help would be greatly appreciated.

Answer 1

. inside a character class ([]) matches itself — it is no longer a wildcard. Also, regular expressions are case sensitive unless told otherwise (“i” flag) and : (in that context) is not special so it does not need to be escaped.

[a-z] or \w might be good to use to match the Attribute, depending.

It might then go like:

var catTitle = "color"
var re = new RegExp(catTitle + ':[a-z]+$', "gi")
re.test("Color:Green") // true
re.test("color:Red")   // true
re.test("color: Red")  // false, put perhaps this should be accepted?
re.test("color:")      // false
re.test("foo:bar")     // false

I also changed the qualifier from * to + — note the case of “color:” and how it’s rejected. This will also reject colors in non-English alphabets.

Happy coding.