c# - Escape Special Character in Regex

Question

Is there a way to escape the special characters in regex, such as []()* and others, from a string?

Basically, I'm asking the user to input a string, and I want to be able to search in the database using regex. Some of the issues I ran into are too many)'s or [x-y] range in reverse order, etc.

So what I want to do is write a function to do replace on the user input. For example, replacing ( with (, replacing [ with [

Is there a built-in function for regex to do so? And if I have to write a function from scratch, is there a way to account all characters easily instead of writing the replace statement one by one?

I'm writing my program in C# using Visual Studio 2010

Answer 1

You can use .NET's built in Regex.Escape for this. Copied from Microsoft's example:

string pattern = Regex.Escape("[") + "(.*?)]"; 
string input = "The animal [what kind?] was visible [by whom?] from the window.";

MatchCollection matches = Regex.Matches(input, pattern);
int commentNumber = 0;
Console.WriteLine("{0} produces the following matches:", pattern);
foreach (Match match in matches)
   Console.WriteLine("   {0}: {1}", ++commentNumber, match.Value);  

// This example displays the following output: 
//       [(.*?)] produces the following matches: 
//          1: [what kind?] 
//          2: [by whom?]