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Console Applications
Console Applications are command-line oriented applications
that allow us to read characters from the console, write characters to the console
and are executed in the DOS version. Console Applications are written in code and
are supported by the System.Console namespace.
Example on a Console Application
Create a folder in C: drive with any name (say, examples) and make sure the console
applications which you open are saved there. That's for your convenience. The default
location where all the .NET applications are saved is C:\Documents
and Settings\Administrator\My Documents\Visual Studio Projects. The new project
dialogue looks like the image below.
The following code is example of a console application:
Module Module1
Sub Main()
System.Console.Write("Welcome to Console Applications")
End Sub
End Module
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You run the code by selecting Debug->Start from
the main menu or by pressing F5 on the keyboard. The result "Welcome
to Console Applications" displayed on a DOS window. Alternatively, you can run
the program using the VB compiler (vbc). To do that, go to the Visual Studio. NET
command prompt selecting from
Start->Programs->Visual Studio.NET->Visual Studio.NET
Tools->Visual Studio.NET Command Prompt and type:
c:\examples>vbc example1.vb.
The result, "Welcome to Console Applications" is displayed on a DOS window as shown
in the image below.
Breaking the Code to understand it
Note the first line, we're creating a Visual Basic Module and Modules are designed
to hold code. All the code which we write should be within the Module.
Next line starts with Sub Main(), the entry point of the program.
The third line indicates that we are using the Write method of the System.Console
class to write to the console.
Commenting the Code
Comments in VB.NET begin with a single quote (') character and the statements following
that are ignored by the compiler. Comments are generally used to specify what is going
on in the program and also gives an idea about the flow of the program. The general
form looks like this:
Dim I as Integer
'declaring an integer
Code
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