How to make asp net routing escape route values


ASP.NET is a popular programming language used for building web applications. One of the key features of ASP.NET is its routing , which allows developers to define how URLs are to specific actions or resources in their application. However, sometimes we may encounter situations where we need to escape certain values to ensure proper functionality. In this article, we will explore different techniques to make ASP.NET routing escape route values.

Using URL

One way to escape route values in ASP.NET routing is by using URL encoding. URL encoding replaces special characters with a “%” followed by their ASCII value in hexadecimal format. This ensures that the route values are properly encoded and can be safely passed in the URL.

 routeValue = "Hello World!";
string encodedValue = HttpUtility.UrlEncode(routeValue);

In the above example, we use the HttpUtility.UrlEncode method to encode the route value “Hello World!”. The resulting encoded value will be “Hello%20World%21”. This encoded value can now be safely used in the URL without causing any issues.

Using Custom Route Constraints

Another approach to escape route values in ASP.NET routing is by using custom route constraints. Route constraints us to define for the values that can be matched by a route parameter. By creating a custom route constraint, we can enforce specific encoding or escaping rules for route values.

public class EscapeRouteConstraint : IRouteConstraint
    public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
        if (values.TryGetValue(parameterName, out object value))
            // Perform custom escaping or encoding  here
            values[parameterName] = EscapeValue(value.ToString());
            return true;
        return false;
    private string EscapeValue(string value)
        // Perform custom escaping or encoding logic here
        return value.Replace(" ", "%20");

In the above example, we create a custom route constraint named EscapeRouteConstraint. This constraint implements the IRouteConstraint interface, which requires us to implement the Match method. Inside the Match method, we can perform our custom escaping or encoding logic for the route value.

To use this custom route constraint, we need to register it in our route configuration:

    name: "EscapeRoute",
    url: "escape/{value}",
    defaults: new { controller = "Escape", action = "Index" },
    constraints: new { value = new EscapeRouteConstraint() }

In the above example, we define a route named “EscapeRoute” with a URL pattern of “escape/{value}”. We set the constraint for the “value” parameter to be an instance of our custom EscapeRouteConstraint. This ensures that any value passed in the “value” route parameter will be escaped according to our custom logic.


Escaping route values in ASP.NET routing is essential to ensure proper functionality and security of our web applications. In this article, we explored two different techniques for escaping route values: using URL encoding and using custom route constraints. By applying these techniques, we can special characters or specific encoding requirements in our route values effectively.

Rate this post

Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents