Visual Basic

About to publish my first article

Isaiah D. Williams — Sun, 04 Dec 2005 01:33:00 GMT

It has been along time since I have posted. It has been extremely busy since my last post with school and of course the friendly hurricane Katrina. I will post some pictures from Katrina when I finally get a chance.

I am glad to say that I am about to publish my first article. It has been an extremely long process. I have learned a great deal about how to write an article and what readers actually look for in an article. Oh well, enough with the boring details in a few days I will be publishing an article that introduces generic types in Visual Basic 2005. So keep your eyes on my blog for a link.

The C# VB.Net Battle

Isaiah D. Williams — Tue, 01 Mar 2005 06:59:00 GMT

Since the creation of the .Net Framework developers have been bickering over what language is better. Better is not the best word to use because there is a great deal of myths surrounding VB.Net in regards to its implementation.

I have read stories how several VB6 developers believe that in order to program in .Net it would require C#, VB.Net is only for web development, and that VB is going away. Well, just to set the record straight C#, VB.Net C++.Net, and J# can all be used in programming within .Net, VB.Net can be used in web development and in application development, and VB is not going away.

With the coming release of VS.Net 2005 the public will see that C# supports a handful of new features that VB.Net doesn't support. From my stand point I believe that Microsoft is sticking true to what they have said all along. VB.Net and C# are both languages designed upon the .Net Framework, however, one will a few features the other doesn't. If the languages were the same it wouldn't make any since for Microsoft to maintain both languages.

My stance on the battle is that VB.Net is better of the two langauges. For me it all boils down to the fact I don't like visiting semi-colon land and the simple fact VB is much easier to read/work with than C#.

The battle continues ...

VB2005 :: My makes life simple

Isaiah D. Williams — Mon, 10 Jan 2005 21:33:00 GMT

Throughout previous versions of Visual Basic accomplishing the most simple task took several lines of code. My favorite example of how the My namespace has made life easier is with downloading files. In previous versions of VB.Net the developer had import the System.Net and several other namespaces. The following code is how one might obtain a text file from the internet without using the My namespace

Imports System.Net
Imports System.Net.Sockets

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Cursor = Cursors.WaitCursor

        '-- Create a new Socket for TCP/IP use
        ClientSocket = New Socket(AddressFamily.InterNetwork, _
           SocketType.Stream, ProtocolType.Tcp)
        '-- Create an endpoint to a server on port 80
        Dim EP As New _
        IPEndPoint(IPAddress.Parse("127.0.0.1"), 80) '127.0.0.1 is localhost
        '-- Connect to the Endpoint
        ClientSocket.Connect(EP)
        '-- Send an HTTP string to retrieve a document
        Dim SendThis() As Byte = _
          System.Text.ASCIIEncoding.ASCII.GetBytes("GET /sockets1.txt" & _
          vbCrLf) 'Change the file name
        ClientSocket.Send(SendThis)
        '-- Wait for received data
        Do
            '-- Is data available?
            If ClientSocket.Poll(1, SelectMode.SelectRead) = True Then
                '-- Available property returns number of bytes ready
                ' to be read. You must read into a byte array.
                ' This is because a character can be more than
                ' one byte if Unicode.
                Dim ReceiveThis(ClientSocket.Available) As Byte
                '-- Read the data
                ClientSocket.Receive(ReceiveThis)
                '-- Convert the byte array to an ASCII string
                TextBox1.Text = _
                  System.Text.ASCIIEncoding.ASCII.GetString(ReceiveThis)
                '-- All done!
                Exit Do
            Else
                '-- Allow other processes to occur
                Application.DoEvents()
                '-- Put the PC to sleep for 1 millisecond to avoid
                ' CPU overload
                System.Threading.Thread.Sleep(1)
            End If
        Loop
        '-- Shutdown and Close the socket. You must always do this
        ClientSocket.Shutdown(SocketShutdown.Both)
        ClientSocket.Close()

        Cursor = Cursors.Default
    End Sub

Roughly twenty-five lines, of actually, code can be condensed to one line. Please note that the code above only displays the text received in a text box. Whereas, the code below will actually download the file to your physical disk.

My.Computer.Network.DownloadFile(”http://127.0.0.1/VBRocks.txt”, “C:\My Documents\VBRocks.txt”)

My is one of several new features that we have to look forward to. What is your favorite feature of My?

How high is too high?

Isaiah D. Williams — Wed, 29 Dec 2004 17:56:00 GMT

Today I was listening to several presentations on Whidbey and the new features that Microsoft has added. These additions were taken straight from customer feedback which has made this an execellent product. However, are we asking for a language that is too high level based.

I have been wondering for some time now what would be my response if I were asked “Do you think that Microsoft has made Visual Basic too high level?” My response to these is rather simple - I believe that Microsoft has developed a language that is at several different levels. What I mean is that there are all these fancy controls and namespaces such as My, however, these additions were added to help bring back RAD and make learning easier for beginners and those programmers that are moving from VB6.

The beautiful thing about .Net is that it can have all these namespaces and controls but the programmer doesn't have to use them. The programmer can still developed their own controls and namespace and move a way from the idea of high level.

How high is too high for Visual Basic?

Plugin' the Holes!

Isaiah D. Williams — Sun, 22 Aug 2004 13:25:00 GMT

Having programmed in Visual Basic for a little over three years gives me a keen eye for the holes in others and likewise the holes in Visual Basic. I believe that each language is designed with a single purpose in mind and each language is catered to that purpose.

In school I am taking AP Computer Science and the curriculum is java programming. After the first few days I began to think that the people who designed java got half way through and just decided to throw in the towel. Having completed the second week of that class I am starting to think that java has too many holes to be used for anything.

This is where Visual Basic .Net 2005 comes into the picture. If I am going to have to use a language I want it to have some of the basic features. Java is lacking several different minor features. So I took the liberty of writing a for-each loop in Visual Basic .Net 2005.

Public Class VBforeach(Of c As {CollectionBase, New}, t)

Public Delegate Sub foreachd(ByVal colType As t)

Public Sub New()

MyBase.New()

End Sub

Public Sub foreach(ByVal collection As c, ByVal colType As t)

Dim handler As foreachd = AddressOf DelegateAction

For Each colType In collection

handler.Invoke(colType)

End Sub

Public Overridable Sub DelegateAction(ByVal colType As t)

' If this prints then there is not overrides

System.Console.WriteLine("Hello, World")

System.Console.ReadLine()

End Sub

End Class

Now I know there is a select few people out there saying that this just some VB programmer ranting. After all this code can only run on a Windows based pc that has .Net Framework 2.0 installed. In all honsety this can be done in any other language so there is no point in getting angry about this.

This is just the beginning ...

Generics in .Net 2005

Isaiah D. Williams — Thu, 05 Aug 2004 11:36:00 GMT

A generic class declaration is a declaration that requires type parameters to be supplied in order to form types. Declaring a class in this way makes the class more robust and gives you more power over what goes on within the class. Constraints allow you to control the argument that is passed to the class. If you set a constraint of IComparable then the argument you passed must implement that Interface.

Using generics with collections make it easier to design a single collection for several types. Let’s say that you have a called “vbCity” and another “MicrosoftVB” and you want to use them with a strong-typed collection. For example purposes the collection class name will be “GenericCollection.” Using generic with the GenericCollection class allows you to use that same class for both our vbCity and MicrosoftVB classes. Below is our GenericCollection class with two constraints IComparable and New, the New constraint requires the argument to have a constructor.

Public Class GenericCollection(Of t As {IComparable, New})

Inherits CollectionBase

' Default constructor

Public Sub New()

MyBase.New()

End Sub

' Add a new item to the collection

Public Function Add(ByVal value As t) As Int32

Return MyBase.InnerList.Add(value)

End Function

' Insert item item to the collection

Public Sub Insert(ByVal index As Int32, ByVal value As t)

MyBase.InnerList.Insert(index, value)

End Sub

' Remove an item from the list

Public Sub Remove(ByVal value As t)

MyBase.InnerList.Remove(value)

End Sub

' Sort the collection

Public Sub Sort()

MyBase.InnerList.Sort()

End Sub

' Check if collection contains item

Public Function Contains(ByVal value As t) As Boolean

Return MyBase.InnerList.Contains(value)

End Function

' Setup the default property to Item

Default ReadOnly Property Item(ByVal index As Int32) As t

Get

' Avoid Late-Binding and return this as t type

Return CType(Me.InnerList.Item(index), t)

End Get

End Property

End Class

Notice that everywhere that t is used in the above example will be replaced during runtime with the type of the argument passed to the class. This is how generics make code more robust and reusable. Below is our vbCity class that meets the requirements of the constraints, it implements IComparable and it has a default constructor.

Public Class vbCity

Implements IComparable

Private _userID As Int32

Public Sub New()

MyBase.New()

End Sub

Public Property UserID() As Int32

Get

Return _userID

End Get

Set(ByVal value As Int32)

_userID = value

End Set

End Property

Public Function CompareTo(ByVal obj As Object) As Integer Implements System.IComparable.CompareTo

Dim vc As vbCity

If obj Is Nothing Then

Return 1

End If

vc = CType(obj, vbCity)

Return vc.CompareTo(vc.UserID)

End Function

End Class

Now that you have your collection class and your vbCity class setup we have to utilize the code that we just wrote. We do so with the following code

Public Sub BuildCollection()

Dim gcc As New GenericCollection(Of vbCity)

Dim vc As vbCity

For i As Integer = 0 To 3

vc = New vbCity

vc.UserID = i

gcc.Add(vc)

End Sub

This is just starching the tip of generics. The designers of .Net have done an excellent job in designing the FCL.