.NET Questions

In WF 4.0, the following two types of workflows are used:

 
     Flowchart workflows - Helps you to create workflows using the common flowchart elements. In WF, the Flowchart activity is generally used to implement a non-sequential workflow, and occasionally it implements sequential workflows in case the FlowDecision nodes are not used. The Flowchart activity contains a collection of flow nodes, which inherit from the FlowNode class. The following types of nodes or elements can be a part of a flowchart:
                 => FlowStep - Executes activities of a flowchart in a sequence.
                 => FlowDecision - Shows the execution on the basis of a Boolean condition.   It is similar to the If construct.
                 => FlowSwitch - Shows the execution on the basis of an exclusive switch. It is similar to the Switch construct.


      Procedural workflows - Helps you to create workflows using basic and sequential execution standards. In WF, procedural workflows use flow control constructs, such as While, Switch, ForEach, and If, to execute activities. These flow control constructs are similar to those found in procedural languages. Procedural workflows can also contain other flow control activities, such as Flowchart and Sequence.

These objects provide two levels of scope:

Application State

Data stored in the application object can be shared by all the sessions of the application.

Application object stores data in the key value pair.

ASP.NET is a specification developed by Microsoft to create dynamic Web applications, Web sites, and Web services. It is a part of .NET Framework. You can create ASP.NET applications in most of the .NET compatible languages, such as Visual Basic, C#, and J#. The ASP.NET compiles the Web pages and provides much better performance than scripting languages, such as VBScript. The Web Forms support to create powerful forms-based Web pages. You can use ASP.NET Web server controls to create interactive Web applications. With the help of Web server controls, you can easily create a Web application.

It is the folder that contains web applications. The folder that has been published as virtual folder by IIS can only contain web applications

Validation controls are responsible to validate the data of an input control. Whenever you provide any input to an application, it performs the validation and displays an error message to user, in case the validation fails.

ASP.NET 4.0 contains the following six types of validation controls:

   => CompareValidator - Performs a comparison between the values contained in two controls.
   => CustomValidator - Writes your own method to perform extra validation.
   => RangeValidator- Checks value according to the range of value.
   => RegularExpressionValidator - Ensures that input is according to the specified pattern or not.
   =>  RequiredFieldValidator - Checks either a control is empty or not.
   => ValidationSummary - Displays a summary of all validation error in a central location.

Any code written in any .NET complaint languages when compiled, converts into MSIL (Microsoft Intermediate Language) code in form of an assembly through CLS, CTS. IL is the language that CLR can understand. On execution, this IL is converted into binary code by CLR’s just in time compiler (JIT) and these assemblies or DLL are loaded into the memory.

.NET Framework is a complete environment that allows developers to develop, run, and deploy the following applications:

 => Console applications
 => Windows Forms applications
 => Windows Presentation Foundation (WPF) applications
 => Web applications (ASP.NET applications)
 => Web services
 => Windows services
 => Service-oriented applications using Windows Communication Foundation (WCF)
 => Workflow-enabled applications using Windows Workflow Foundation (WF)

State is quite an innovative concept in Web development because it eliminates the drawback of losing state data due to reloading of a Web page. By using states in a Web application, you can preserve the state of the application either at the server or client end. The state of a Web application helps you to store the runtime changes that have been made to the Web application. For example, as already described earlier, a change in the data source of the Web application might be initiated by a user when he/she selects and saves some products in the shopping cart.

If you are not using states, these changes are discarded and are not saved. You may think that the whole concept of storing states is optional. However, under certain circumstances, using states with applications is imperative. For example, it is necessary to store states for Web applications, such as an e-commerce shopping site or an Intranet site of a company, to keep track of the requests of the users for the items they have selected on the shopping site or the days requested for vacation on the Intranet site.