Escaping regular expression characters in an input string
When using input gathered from a user to create a regular expression, the user input may contain regular expression control characters such as ‘.’ and ‘*’. These need to be escaped so the regular expression engine treats them as literal characters.
Here’s on way to do it:
re = new RegExp(‘^’ + selection.replace(/[-[\]{}()*+?.,\\^$|#\s]/g, “\\$&”) + ‘$’, ‘i’);
This is an example for Javascript. The example uses the option to pass the String.replace() method a regular expression containing an array of characters and prepends any with a leading backslash (that’s the “\\$&” sequence). The ‘g’lobal flag is used to ensure each occurrence is updated.
