Answers For Great Net Developer (3)

Answers For Great .Net Developer (3)
ASP.NET (UI) Developers

• Describe how a browser-based Form POST becomes a Server-Side event like Button1_OnClick. After a button click event happened, the delegate will call a associated method with this event (this method is called event handler) . Common Scenario: Postback event--->page_Load(ispostback=false) ---> Buttoin_Click--->Raise Postback event--->Page_Load(ispostback=true, )-----> Call Event Handler method
• What is a PostBack?


• For server control to capture postback event, it must implant .IPostBackEventHandler Interfaces.


• On postback, the page framework searches the post content and determines whether a posted name corresponds to the unique id of a server control that implements IPostBackEventhandler. If so, it invokes the RaisePostBackEvent method of that control.


• What is ViewState? How is it encoded? Is it encrypted? Who uses ViewState?


• In ASP, the state can not be stored in web. So have to use hidden fileld to store values.


• ViewState is not only page based. It can be controlled in four levels: Machine , application(web.config), page, control.


• Base64 formatted. Default is not encrypted but can be by adding some code. A convenient way to manage the state.


• It can become pretty big if there are a lot of controls in the page or the control has a lot of information to store (like datagrid).


• What is the <machinekey> element and what two ASP.NET technologies is it used for?


• What three Session State providers are available in ASP.NET 1.1? What are the pros and cons of each?


• What is Web Gardening? How would using it affect a design?


• Given one ASP.NET application, how many application objects does it have on a single proc box? A dual? A dual with Web Gardening enabled? How would this affect a design?


• Are threads reused in ASP.NET between reqeusts? Does every HttpRequest get its own thread? Should you use Thread Local storage with ASP.NET?


• Is the [ThreadStatic] attribute useful in ASP.NET? Are there side effects? Good or bad?


• Give an example of how using an HttpHandler could simplify an existing design that serves Check Images from an .aspx page.


• What kinds of events can an HttpModule subscribe to? What influence can they have on an implementation? What can be done without recompiling the ASP.NET Application?


• Describe ways to present an arbitrary endpoint (URL) and route requests to that endpoint to ASP.NET.


• Explain how cookies work. Give an example of Cookie abuse.


• A cookie is a piece of information sent to a browser by the server. Then browser sends it back to server. By this way, the server will remember the user old info like user name, age, etc .


• Big cookies will affect the traffic of network and security issue.


• Explain the importance of HttpRequest.ValidateInput()?


• What kind of data is passed via HTTP Headers?


• Juxtapose the HTTP verbs GET and POST. What is HEAD?


• Name and describe at least a half dozen HTTP Status Codes and what they express to the requesting client.


• How does if-not-modified-since work? How can it be programmatically implemented with ASP.NET?Explain <@OutputCache%> and the usage of VaryByParam, VaryByHeader.


• How does VaryByCustom work?


• How would one implement ASP.NET HTML output caching, caching outgoing versions of pages generated via all values of q= except where q=5 (as in http://localhost/page.aspx?q=5)?