URL regex C#

URL regex C#

URL regular expressions can be used to verify if a string has a valid URL format as well as to extract an URL from a string.

URL regex that starts with HTTP or HTTPS

HTTP and HTTPS URLs that start with protocol can be validated using the following regular expression

new Regex("^https?:\\/\\/(?:www\\.)?[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)$")

Test it!
/^https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/

True

False

Enter a text in the input above to see the result

Example code in C#:

using System.Text.RegularExpressions;
using System.Linq;
using System;
                    
public class Program
{
    public static void Main()
    {
        // Validate URL
        Regex validateDateRegex = new Regex("^https?:\\/\\/(?:www\\.)?[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)$");
        Console.WriteLine(validateDateRegex.IsMatch("https://uibakery.io"));  // prints True
        
        // Extract URL from a string
        Regex extractDateRegex = new Regex("https?:\\/\\/(?:www\\.)?[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)");
        string [] extracted = extractDateRegex.Matches("You can view more details at https://uibakery.io or just ping via email.")
            .Cast<Match>()
            .Select(m => m.Value) 
            .ToArray(); 
        Console.WriteLine(String.Join(",", extracted)); // prints https://uibakery.io
    }
}

URL regex that doesn’t start with HTTP or HTTPS

The regular expression to validate URL without protocol is very similar:

new Regex("^[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)$")

Test it!
/^[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)$/

True

False

Enter a text in the input above to see the result

Example code in C#:

using System.Text.RegularExpressions;
using System.Linq;
using System;
                    
public class Program
{
    public static void Main()
    {
        // Validate URL without protocol
        Regex validateDateRegex = new Regex("^[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)$");
        Console.WriteLine(validateDateRegex.IsMatch("uibakery.io/contact"));  // prints True
        
        // Extract URL without protocol from a string
        Regex extractDateRegex = new Regex("[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&\\/=]*)");
        string [] extracted = extractDateRegex.Matches("You can view more details at uibakery.io or just ping via email.")
            .Cast<Match>()
            .Select(m => m.Value) 
            .ToArray(); 
        Console.WriteLine(String.Join(",", extracted)); // prints uibakery.io
    }
}

Test it!

True

False

Enter a text in the input above to see the result

Notes on URL validation

The above-mentioned regular expressions only cover the most commonly used types of URLs with domain names. If you have some more complex cases you might need a different solution.