Vb.Net Programmes

Public Class Form1
         Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click

         Dim i As Integer
         Dim week(6) As String week(0) = "Sunday" week(1) = "Monday" week(2) = "Tuesday" week(3) = "Wednesday" week(4) = "Thursday" week(5) = "Friday" week(6) = "Saturday"

 For i = 0 To week.Length - 1

 MsgBox(week(i))

Next
    End Sub
End Class

CheckBox Control

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

If CheckBox1.Checked = True Then

Literal1.Text = "You Checked the Box"

Else

Literal1.Text = "You Did Not Check the Box"

End If

End Sub

Public Class Form1

 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
  Dim msg As String = ""

  If CheckBox1.Checked = True Then
   msg = "net-informations.com"
  End If

  If CheckBox2.Checked = True Then
   msg = msg & "   vb.net-informations.com"
  End If

  If CheckBox3.Checked = True Then
   msg = msg & "   csharp.net-informations.com"
  End If


  If msg.Length > 0 Then
   MsgBox(msg & " selected ")
  Else
   MsgBox("No checkbox selected")
  End If

  CheckBox1.ThreeState = True
 End Sub

Multi-Dimensional Array: VB.Net मे कई dimensions के array create किए जा सकते हैं। ऐसे arrayजिसमे एक से जायदा subscripts होती हैं उन्हे multi-dimensional array कहते हैं। MD array कोdeclare करने के लिए भी Dim, private या public statement का use किया जाता है। इसे declare करते समय इसमे एक से ज्यादा subscripts दी जाती हैं। यह subscripts के multiple के बराबर values storeकर सकते हैं जैसे n(2,3) array मे 6 values store की जा सकती हैं।

Syntax:

Dim <array name> (script1, script2 ...) As <Data Type>

Exp-

Dim matrix (3, 3) as Integer

Dim T (2, 3, 4, 2) As Double

Initializing Multi-Dimensional Array:

MD Array को initialize करने के लिए Carly braces का use करते हैं।

Dim n (3, 3) As Integer = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}

Public Class Form1

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

        Dim mat(3, 3) As Integer

        Dim i, j As Integer

        'Take Input

        For i = 0 To 2

            For j = 0 To 2

                mat(i, j) = InputBox("Enter value on Matrix")

            Next

        Next

        'Printing Matrix

        Label1.Text = ""

        For i = 0 To 2

            For j = 0 To 2

                Label1.Text = Label1.Text & "   " & mat(i, j)

            Next

            Label1.Text = Label1.Text & Chr(13)

        Next

    End Sub

End Class

How to Use ForEach loop with Arrays ?

Public Class Form1

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

Dim array As Integer() = {10, 30, 50}

 For Each element As Integer In array

MsgBox(element)
Next

End Sub

 End Class

Optional Arguments:

VB.Net मे optional arugments भी दिये जा सकते है। optional arguments देने के लिए argument को declareकरते समय Byval/ Byref keyword के पहले Optional keyword का use किया जाता है और इसमे default value दी जाती है। Default value देना compulsory होता है। जिसका syntax निम्न है।

[Optional] [Byval / ByRef] <variable_name> As <Data Type> = <Default Value>

Ex-

Private Function Sum(ByVal a As Integer, Optional ByVal b As Integer = 10) AsInteger

        Return (a + b)

End Function

 Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles Button1.Click
    Dim totalMarks As Integer
    totalMarks = 59
    If totalMarks >= 80 Then
        MsgBox("Gor Higher First Class ")
    ElseIf totalMarks >= 60 Then
        MsgBox("Gor First Class ")
    ElseIf totalMarks >= 40 Then
        MsgBox("Just pass only")
    Else
        MsgBox("Failed")
    End If
End Sub
End Class

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, 
 ByVal e As System.EventArgs) Handles Button1.Click
        Dim totalMarks As Integer
        totalMarks = 39
    If totalMarks >= 50 Then MsgBox("passed ") Else MsgBox("Failed ")
    End Sub
End Class

   Dim x As Integer 
        x = 10 
        If (x Mod 2) = 0 Then 
            Console.WriteLine("x is an even number") 
        Else 
            Console.WriteLine("x is an odd number") 
        End If 
        Console.ReadLine() 
    End Sub 

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object,
 ByVal e As System.EventArgs) Handles Button1.Click
        Dim var As Integer
        Dim startVal As Integer
        Dim endVal As Integer
        startVal = 1
        endVal = 5
        For var = startVal To endVal
            MsgBox("Message Box Shows " &   var &   " Times ")
        Next var
    End Sub
End Class

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, 
 ByVal e As System.EventArgs) Handles Button1.Click
        Dim counter As Integer
        counter = 1
        While (counter <= 10)
            MsgBox("Counter Now is : "  counter)
            counter = counter + 1
        End While
    End Sub

 If….Then…ElseIf Statement

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim Mark As Integer
Dim Grade as String
 Mark = TextBox1.Text
 If myNumber >=80 Then
  Grade="A"
 ElseIf Mark>=60 and Mark<80 then
  Grade="B"
 ElseIf Mark>=40 and Mark<60 then
  Grade="C"
 Else
  Grade="D"
 End If
End Sub

Select Case

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

'Examination Marks
Dim mark As Single
mark = TextBox1.Text
Select Case mark
 Case 0 To 49
  Label1.Text = "E"
 Case 50 To 59
  Label1.Text = "D"
 Case 60 To 69
  Label1.Text = "C"
 Case 70 To 79
  Label1.Text = "B"
 Case 80 To 100
  Label1.Text = "A"
 Case Else
  Label1.Text = "Error, please reenter the mark"
End Select
End Sub

For….Next Loop
Dim counter as Integer
 For counter=1 to 10
  ListBox1.Items.Add (counter)
 Next


* The program will enter number 1 to 10 into the list box.

Dim counter , sum As Integer
 For counter=1 to 100 step 10
  sum+=counter
  ListBox1.Items.Add (sum)
 Next



* The program will calculate the sum of the numbers as follows:


sum=0+10+20+30+40+……

Dim counter, sum As Integer
sum = 1000
 For counter = 100 To 5 Step -5
  sum - = counter
  ListBox1.Items.Add(sum)
Next



*Notice that increment can be negative.


The program will compute the
subtraction as follow:
1000-100-95-90-……….

Dim n as Integer
For n=1 to 10
 If n>6 then
  Exit For
 End If
 Else
  ListBox1.Items.Add ( n)
Next

The process will stop when n is greater than 6.


Timer Control 



Public Class Form1
    Dim second As Integer

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Timer1.Interval = 1000
        Timer1.Start() 'Timer starts functioning
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Label1.Text = DateTime.Now.ToString

        second = second + 1
        If second >= 10 Then
            Timer1.Stop() 'Timer stops functioning
            MsgBox("Timer Stopped....")
        End If

    End Sub

End Class