Route.Constraints Property
Gets or sets a dictionary of expressions that specify valid values for a URL parameter.
Assembly: System.Web (in System.Web.dll)
Property Value
Type: System.Web.Routing.RouteValueDictionaryAn object that contains the parameter names and expressions.
The Constraints property enables you to limit acceptable values for a URL parameter that is processed by a route. You assign a RouteValueDictionary object to the Constraints property. Each element in the RouteValueDictionary object contains the name of a parameter and one of the following:
A string that defines a regular expression. The regular expression is case-insensitive.
An object that implements the IRouteConstraint interface and that includes a Match method.
The HttpMethodConstraint class implements the IRouteConstraint interface. You can include an instance of the HttpMethodConstraint class as a constraint to specify which HTTP verbs are acceptable for the route.
The following example shows how to create a Route object and set the Constraints, DataTokens, and Defaults properties.
The following example shows a Route object whose Constraints property contains a parameter named httpMethod with an instance of the HttpMethodConstraint class for the value.
Available since 3.5