Using a string variable as regular expression

Question

In JavaScript, we append /g to an unquoted string to denote a regular expression.

What if I have a string in a variable and want to use it as a regular

Answer 1

Thanks, Gabi, you helpmed a lot. However, I had to put the regexp part (the variable part) without quotes to make it work:

new RegExp(yourRegExp, "modifiers").

I hope this helps someone.

Answer 2

Use this:

new RegExp("your regex here", "modifiers");

And notice that /g is not the delimiter for a regex, it is global modifier. A regex looks like this: /your regex here/modifiers. modifiers can be a combination of g, i and m. They are all explained here: http://www.regular-expressions.info/javascript.html

Answer 3

/g is a flag denoting global ( match all instances of the regex ), it doesn't denote a regular expression but is simply a flag.

If you want a dynamic regex use new RegExp. Usage here: https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/RegExp