MSDN Magazine Issues and Downloads. Read the magazine online, download a formatted digital version of each issue, or grab sample code and apps. If you are dealing with ASP. NET that invokes the compiler automatically for you, you can control the encoding used by specifying this on the web config file. Server Implementation Comparison Creating a Server in. Ugly Betty 4 Temporada Dublado here. NET Remoting. NET Remoting server types must derive from MarshalByRefObject and define methods the client can. Unhandled exceptions in the Web API controller class are often indicated as HTTP status code 500, i. Internal Server Error. This generic error message is of little. Sample report Custom viewsfilters Servers list, organized in groups Integration with EventID. Net Consolidated view for all logs Free for subscribers. NOTE This document has not been updated for some time, and much of the material is outofdate. I am not planning any further updates. NET Framework FAQ. UOgqE3fGXc/StiBidnnSQI/AAAAAAAABZk/YZkb176361k/image_thumb%5B6%5D.png?imgmax=800' alt='Net Remoting Serialization Exception' title='Net Remoting Serialization Exception' />Handling Exceptions in ASP. NET Web APIWEBINAR On demand webcast. How to Boost Database Development Productivity on Linux, Docker, and Kubernetes with Microsoft SQL Server 2. ServiceContract OperationContract ListltCampaign AttainCampaigns Works when Instantiating Objects Directly public ListltCampaign AttainCampaigns. From programming procedures to developer tools, our programming dictionary offers a glossary of terms you need to know. PDF files that contain the Visual Studio 2005 documentation. VB. Net Quick Guide Learn VB. Net Programming in simple and easy steps starting from Environment setup, Basic Syntax, Data Types, Type Conversion, Variables. REGISTER Introduction. Whenever there is any unhandled exception in Web API controller class, most of the actual exceptions are indicated as HTTP status code 5. Internal Server Error. This generic error message is of little use to the client as it doesnt reveal the actual cause of the server side error. However, Web API allows you to fine tune and customize the HTTP errors that are sent to the client browser. This article discusses how this is done. Throwing Exceptions from an API Controller. Consider a Web API controller named Customer. Controller as shown below public class Customer. Controller Api. Controller. Customer Getstring id. Northwind. Entities dbnew Northwind. Entities. var data from item in db. Customers. where item. Customer. ID id. Customer obj data. Single. Or. Default. ExceptionCustomer. ID Not Found in Database. The Customer. Controller class uses the Customers table of the Northwind database. The above code shows only the Get method of the Customer. Controller class. The Get method accepts a Customer. ID and returns a Customer object matching the specified Customer. ID. If there is no Customer entry for the specified Customer. ID, an exception is thrown with message Customer. ID Not Found in Database. To invoke the Get method from the client side you can use the j. Query. ajax method as shown below. Customer. data id txt. Customer. ID. val. Type applicationjson charsetutf 8. Type json. success function result. Customer. ID result. Company. Name. error function err,type,http. Status. alerterr. Text http. Status. Since you are invoking the Get method, the. GET as the request type. The url is specified as apiCustomer. Based on the request type and the URL, the Web API framework will invoke the Get method of Customer API controller. The Get method takes one parameter Customer. ID. The Customer. ID is grabbed from a textbox txt. Customer. ID in the above example and is wrapped in an object literal with key id. This key name must be the same as the parameter name. If the Get method completes successfully, a function as specified by the success setting is called. The success function receives the Customer object returned by the Get method. The success method simply displays the Customer. ID and Company. Name property values of the Customer object. The error function is called in case there is any error while invoking the Get method. The error function receives three parameters, viz. HTTP status. If you run the above code and supply some Customer. ID that doesnt exist, you will get an error message as shown below 5. Error Internal Server Error. As you can see, though the server side exception message is Customer. ID Not Found in Database the client always shows the error message as Internal Server Error. Using Http. Response. Exception Class to Throw Exceptions. To emit some meaningful error messages to the client you can use the Http. Response. Exception class. Lets see how the Get method can be modified using the Http. Response. Exception class. Have a look at the code below public Customer Getstring id. Northwind. Entities dbnew Northwind. Entities. var data from item in db. Customers. where item. Customer. ID id. Customer obj data. Single. Or. Default. Http. Response. Message msg new Http. Response. MessageHttp. Status. Code. Not. Found. Content new String. Contentstring. FormatNo customer with ID 0, id. Reason. Phrase Customer. ID Not Found in Database. Http. Response. Exceptionmsg. Notice the code marked in bold letters. The code creates an instance of Http. Response. Message class by specifying HTTP status code as Not. Found i. e. 4. 04. It also sets the Content and Reason. Phrase properties to a custom error message. The Content property specifies the response text whereas the Reason. Phrase property controls the descriptive text accompanying the status code. Finally, an Http. Response. Exception is thrown by passing the Http. Response. Message instance that you just created. If you run the modified version of Get method and supply some nonexistent Customer. ID you will get an error message like this 4. Error. As you can see, this time the client gets the custom error message as specified by the Response. Phrase property in the code instead of the standard message Internal Server Error. If you observe the HTTP response in Chrome Developer Tools you will see something like this HTTP response in Chrome Developer Tool. Writing a Custom Exception Filter to Process Unhandled Exceptions. In the modified version of the Get method you checked some condition and based on the outcome of the condition Http. Response. Exception was thrown. However, at times there can be unhandled exceptions in the code. These unhandled exceptions too dont generate any meaningful error message for the client. To deal with such unhandled exceptions you can create an Exception Filter. An exception filter is a class that implements the IException. Filter interface. To create a custom exception filter you can either implement the IException. Filter interface yourself or create a class that inherits from the inbuilt Exception. Filter. Attribute class. In the later approach all you need to do is override the On. Exception method and plug in some custom implementation. The following code shows how this is done. My. Exception. Filter Exception. Filter. Attribute. On. ExceptionHttp. Action. Executed. Context context. Http. Response. Message msg new Http. Response. MessageHttp. Status. Code. Internal. Server. Error. Content new String. ContentAn unhandled exception was thrown by Customer Web API controller. Reason. Phrase An unhandled exception was thrown by Customer Web API controller. Response msg. As you can see the My. Exception. Filter class inherits from Exception. Filter. Attribute class and overrides the On. Exception method. The On. Exception method is called whenever there is any unhandled exception. The On. Exception method essentially creates a new Http. Response. Message class as discussed earlier and then sets the Response property of the Http. Action. Executed. Context  to the newly created Http. Response. Message object. Using a Custom Exception Filter. Once you develop a custom exception filter you can put it to use in two ways You can register it in the ApplicationStart event of Global. You can decorate the Get  method with the exception filter attribute. To register your custom exception filter using the first technique, add the the following piece of code to the Global. Web. Api. Application System. Web. Http. Application. ApplicationStart. Global. Configuration. Configuration. Filters. Addnew Web. APIExceptions. Demo. My. Exception. Filter. Area. Registration. Register. All. Areas. Notice the line of code marked in bold letters. The custom exception filter is added to the Filters collection using the Global. Configuration class. This way all the methods automatically use the My. Exception. Filter exception filter for dealing with unhandled exceptions. Alternatively, you can also mark the individual methods with the custom exception filter attribute as shown below My. Exception. Filter. Customer Getstring id. As you can see the Get method is now decorated with My. Exception. Filter attribute.