1. VB.Net Programs
Prof. K. Adisesha 1
C# & Dot Net Lab Programs
Part- B
1. VB.net Program to count the number of Vowels in a string
Public Class Form1
Private Sub resultBtn_Click(sender As Object, e As EventArgs) Handles resultBtn.Click
Dim str1, str2 As String
Dim vcount, i, str1len As Integer
vcount = 0
str1 = stringText.Text
str1len = Len(str1)
str1 = LCase(str1)
For i = 1 To str1len
str2 = Mid(str1, i, 1)
If str2 = "a" Or str2 = "e" Or str2 = "i" Or str2 = "o" Or str2 = "u" Then
vcount = vcount + 1
End If
Next i
resultText.Text = vcount
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Close()
End Sub
End Class
3. VB.Net Programs
Prof. K. Adisesha 3
2. VB.net Program to Check a given is Even or Odd Number or Overflow
if number>10000
Code:
Public Class Form1
Private Sub Label2_Click(sender As Object, e As EventArgs) Handles Label2.Click
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles resultBtn.Click
If valueText.Text Mod 2 = 0 Then
resultText.Text = "EVEN"
Else
resultText.Text = "ODD"
End If
If valueText.Text > 10000 Then
resultText.Text = "Overflow!!!"
End If
4. VB.Net Programs
Prof. K. Adisesha 4
End Sub
Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
valueText.Text = ""
End Sub
Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Close()
End Sub
End Class
Output:
5. VB.Net Programs
Prof. K. Adisesha 5
3. VB.net Program to calculate the compound interest
Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles resultBtn.Click
Dim P As Integer
Dim R As Integer
Dim n As Integer
P = principleText.Text
R = rateText.Text
n = timeText.Text
compText.Text = P * (1 + (R / 100)) ^ n - 1
End Sub
Private Sub Button1_Click_1(sender As Object, e As EventArgs) Handles btnExit.Click
Close()
End Sub
6. VB.Net Programs
Prof. K. Adisesha 6
Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
principleText.Text = ""
rateText.Text = ""
timeText.Text = ""
End Sub
End Class
Output:
7. VB.Net Programs
Prof. K. Adisesha 7
4. VB.Net Program to Display the sum of Positive and negative numbers
using input box
Code:
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
End Sub
Private Sub resultBtn_Click(sender As Object, e As EventArgs) Handles resultBtn.Click
Dim arr(), a, b, c, i As Integer
a = CInt(limitText.Text)
ReDim arr(a)
For i = 0 To a - 1 Step 1
arr(i) = CInt(InputBox("Enter elements:"))
If arr(i) > 0 Then
b = b + arr(i)
ElseIf arr(i) < 0 Then
c = c + arr(i)
End If
Next
positiveText.Text = b
negativeText.Text = c
End Sub
8. VB.Net Programs
Prof. K. Adisesha 8
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Close()
End Sub
End Class
Output:
9. VB.Net Programs
Prof. K. Adisesha 9
5. VB.Net Program to concatenate two strings and display result using
Message Box.
Code:
Public Class Form1
Private Sub resultBtn_Click(sender As Object, e As EventArgs) Handles resultBtn.Click
Dim x As String
Dim y As String
x = firstText.Text
y = lastText.Text
MsgBox(firstText.Text + " " + lastText.Text, vbOKCancel)
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Close()
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles btnclear.Click
firstText.Clear()
lastText.Clear()
End Sub
End Class
11. VB.Net Programs
Prof. K. Adisesha 11
6. Write a program to change the style of font based on the user’s
choice by using CHECK BOX BUTTON
Public Class Form1
Private Sub setStyle()
Dim style = FontStyle.Regular
If boldCheck.Checked Then
style = style Or FontStyle.Bold
End If
If italicsCheck.Checked Then
style = style Or FontStyle.Italic
End If
If underLineCheck.Checked Then
style = style Or FontStyle.Underline
End If
inputText.Font = New Font(inputText.Font, style)
End Sub
Private Sub boldCheck_CheckedChanged(sender As Object, e As EventArgs) Handles
boldCheck.CheckedChanged
setStyle()
End Sub
Private Sub italicsCheck_CheckedChanged(sender As Object, e As EventArgs) Handles
italicsCheck.CheckedChanged
12. VB.Net Programs
Prof. K. Adisesha 12
setStyle()
End Sub
Private Sub underLineCheck_CheckedChanged(sender As Object, e As EventArgs)
Handles underLineCheck.CheckedChanged
setStyle()
End Sub
End Class
Output:
13. VB.Net Programs
Prof. K. Adisesha 13
7. Write a program to generate a Student Enrolment Details form using
Combo box.
Code:
Public Class Form1
Private Sub dispBtn_Click(sender As Object, e As EventArgs) Handles dispBtn.Click
MsgBox("These are the following details entered: " + vbCrLf + " Name:" + nameText.Text + vbCrLf
+ "Course:" + courseCombo.Text + vbCrLf + "Semester:" + semCombo.Text + vbCrLf + "Marks:" +
marksText.Text, vbOKOnly)
End Sub
Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
Close()
End Sub
End Class
15. VB.Net Programs
Prof. K. Adisesha 15
8. Write a program to generate a Dynamic User login form using
Database.
Code:
Note: Follow the following steps:
➢ Provide MySQL password
➢ Create a Database and provide DB name in Inputbox.
➢ Login table will be created with the given Name in Inputbox
Imports System.Data.Odbc
Public Class Form1
Dim uname As String = InputBox("Enter the UserName of MySql:")
Dim pass As String = InputBox("Enter the password of MySql:")
Dim dB As String = InputBox("Enter the DataBase name")
Dim connectionString As String = "DRIVER={MySQL ODBC 8.0 Unicode
Driver};SERVER=localhost;DATABASE=" + dB + ";UID=" + uname + ";PASSWORD=" + pass
+ ";OPTION=3;"
Public conn As New OdbcConnection(connectionString)
Dim sqlTableCreate As String = "CREATE TABLE users(username varchar(25),password
varchar(25));"
Dim cmdCreate As New OdbcCommand(sqlTableCreate, conn)
16. VB.Net Programs
Prof. K. Adisesha 16
Sub Open()
cmdCreate.ExecuteNonQuery()
End Sub
Private Sub createBtn_Click(sender As Object, e As EventArgs) Handles createBtn.Click
Try
If unameText.Text = "" Or passText.Text = "" Then
MsgBox("Please Provide the values", vbExclamation)
Else
conn.Open()
Dim rows As Integer
Dim sqlInsert As String = "INSERT INTO users(username,password) values(" + "'"
+ unameText.Text + "','" + passText.Text + "')"
Dim cmd As New OdbcCommand(sqlInsert, conn)
rows = cmd.ExecuteNonQuery()
If rows > 0 Then
MsgBox("User Created!", vbOK)
End If
End If
conn.Close()
Catch ex As Exception
MsgBox("Database Error", vbExclamation)
End Try
End Sub
Private Sub loginBtn_Click(sender As Object, e As EventArgs) Handles loginBtn.Click
Try
conn.Open()
Dim sqlSelect As String = "SELECT username,password FROM users WHERE
username=" + "'" + unameText.Text + "' AND " + "password='" + passText.Text + "'"
Dim cmd As New OdbcCommand(sqlSelect, conn)
Dim sqlResult As OdbcDataReader
sqlResult = cmd.ExecuteReader()
If sqlResult.HasRows Then
MsgBox("User Successfully Logged In", vbOK)
conn.Close()
Else
MsgBox("No Match found", vbExclamation)
conn.Close()
End If
Catch ex As Exception
MsgBox("DataBase Error", vbCritical)
End Try
17. VB.Net Programs
Prof. K. Adisesha 17
End Sub
Private Sub clearBtn_Click(sender As Object, e As EventArgs) Handles clearBtn.Click
unameText.Clear()
passText.Clear()
End Sub
Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles
showPassCheck.CheckedChanged
If showPassCheck.CheckState = CheckState.Unchecked Then
passText.PasswordChar = "*"
ElseIf showPassCheck.CheckState = CheckState.Checked Then
passText.PasswordChar = ""
End If
End Sub
End Class
Output:
18. VB.Net Programs
Prof. K. Adisesha 18
9. Program to Implement MDI (Multiple Document Interface) Parent Form
Follow the following Steps
➢ To make a form as MDI Form set its IsMdiContainer property as true.
➢ To define a parent form to a child form set MdiParent property.
➢ To arrange the child forms, use LayoutMdi() method.
➢ To get reference of the current child form use ActiveMdiChild property.
➢ To get reference of a control from the child form use its Controls collection.
Output: