VB.NET Programs. ADO.NET (insert, update, view records)

Transcription

1 ADO.NET (insert, update, view records) VB.NET Programs Database: Student Table : Studtab (adno, name, age, place) Controls: DataGridView, Insert button, View button, Update button, TextBox1 (for Admission No), TextBox2 (for Name), TextBox3 (for Age), TextBox4 (for Place) Imports System.Data Imports System.Data.SqlClient Public Class DB Dim myconnection As SqlConnection Dim mycommand As SqlCommand Private Sub DB_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 'TODO: This line of code loads data into the 'StudentDataSet.Studtab' table. You can move, or remove it, as needed. Me.StudtabTableAdapter.Fill(Me.StudentDataSet.Studtab) Private Sub InsertBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles InsertBtn.Click myconnection = New SqlConnection("Data Source=ASUS-PC\SQLEXPRESS; Initial Catalog=Student;Integrated Security=True;Pooling=False") myconnection.open() mycommand = New SqlCommand("insert into Studtab(adno,name,age,place) values ('" & TextBox1.Text & "','" & TextBox2.Text & "','" & TextBox3.Text & "','" & TextBox4.Text & "')", myconnection) mycommand.executenonquery() MessageBox.Show("New Row Inserted") myconnection.close() Private Sub UpdateBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles UpdateBtn.Click myconnection = New SqlConnection("Data Source=ASUS- PC\SQLEXPRESS;Initial Catalog=Student;Integrated Security=True;Pooling=False") myconnection.open() mycommand = New SqlCommand("UPDATE Studtab SET name = '" & TextBox2.Text & "', age = '" & TextBox3.Text & "', place ='" & TextBox4.Text & "' where adno=" & TextBox1.Text & "", myconnection) mycommand.executenonquery() MessageBox.Show("One Record Modified") myconnection.close() Private Sub ViewBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ViewBtn.Click Me.StudtabTableAdapter.Fill(Me.StudentDataSet.Studtab)

2 Class & Object (Details of N students) Public Class Student Private adno As Integer Private name As String Private dob As Date Public Property Number() As Integer Get Return adno End Get Set(ByVal value As Integer) adno = value End Set End Property Public Property Nam() As String Get Return name End Get Set(ByVal value As String) name = value End Set End Property Public Property Dbirth() As Date Get Return dob End Get Set(ByVal value As Date) dob = value End Set End Property Controls: Student button, ListBox Public Class ClassObject Private Sub StudentBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles StudentBtn.Click Dim i, n As Byte Dim s(10) As Student n = InputBox("No of Students") For i = 0 To n - 1 s(i) = New Student s(i).number() = InputBox("Admission No : ") s(i).nam() = InputBox("Name : ") s(i).dbirth() = InputBox("Date of Birth") For i = 0 To n - 1 ListBox1.Items.Add(s(i).Number().ToString & vbtab & s(i).nam() & vbtab & s(i).dbirth.tostring("d"))

3 Employee details using structure Controls: Employee Button, ListBox Public Class Emp Structure Employee Dim code As Integer Dim name As String Dim salary As Double End Structure Private Sub EmployeeBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles EmployeeBtn.Click Dim emp As Employee emp.code = InputBox("Enter the code", "Employee Details") emp.name = InputBox("Enter the name", "Employee Details") emp.salary = InputBox("Enter the salary", "Employee Details") ListBox1.Items.Add(emp.code.ToString & vbtab & emp.name & vbtab & vbtab & emp.salary.tostring) Divide-by-zero Exception Controls: TextBox, Division button Public Class Division Private Sub DivisonBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DivisionBtn.Click Dim a As Decimal = InputBox("Enter the dividend") Dim b As Decimal = InputBox("Enter the divisor") Try TextBox1.Text = (a / b).tostring Catch ex As DivideByZeroException TextBox1.Text = "Division of " + a.tostring + " by zero" End Try Image-resize using scrollbars Controls: PictureBox, HScrollBar, VScrollBar Public Class PictureResize Private Sub VScrollBar1_Scroll(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ScrollEventArgs) Handles VScrollBar1.Scroll PictureBox1.Height = e.newvalue Private Sub HScrollBar1_Scroll(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ScrollEventArgs) Handles HScrollBar1.Scroll PictureBox1.Width = e.newvalue

4 Jagged Array Module Module1 Dim y As Integer y = InputBox("No of rows") Jarray(y) Private Sub Jarray(ByVal n As Integer) Dim a()() As Integer = New Integer(n)() {} Dim i, j, k As Integer k = k + 1 For i = 1 To n a(i - 1) = New Integer(i - 1) {} For j = 1 To i a(i - 1)(j - 1) = k k = k + 1 Console.Write(a(i - 1)(j - 1)) Console.Write(" ") k = k - 1 Console.WriteLine() MsgBox("End") Palindrome Module Module2 Function palindrome(byval str As String) Dim s1 As String s1 = StrReverse(str) If (s1 = str) Then MsgBox("Palindrome") Else MsgBox("Not Palindrome") End Function Dim s As String s = InputBox("Enter a string") palindrome(s) Strange Numbers Module Module3 Strange(1, 500)

5 Public Sub Strange(ByVal a As Integer, ByVal b As Integer) Dim c, i, r, t As Integer For i = a To b c = i t = 0 While c <> 0 r = c Mod 10 t += r ^ 3 c \= 10 End While If t = i Then Console.WriteLine(i) MsgBox("Strange numbers") Prime Numbers Module Module4 Dim y As Integer y = InputBox("Enter N : ") Prime(y) Private Sub Prime(ByRef n As Integer) Dim c, i, num, fg As Integer num = 2 While c < n fg = 1 For i = 2 To num ^ 0.5 If num Mod i = 0 Then fg = 0 Exit For If fg = 1 Then Console.WriteLine(num) c += 1 num += 1 End While MsgBox("Prime numbers") Case Conversion Module Module5 Dim s As String s = InputBox("Enter a string") CaseConv(s)

6 Private Sub CaseConv(ByVal str As String) Dim c As Char Dim i As Integer For i = 1 To str.length c = GetChar(str, i) If Char.IsLower(c) Then Console.Write(c.ToString.ToUpper()) Else Console.Write(c.ToString.ToLower()) MsgBox("End") Vowel Module Module6 Dim z As Char z = InputBox("Enter a character", "Vowel", "a", 50, 50) z = z.tostring.tolower() If z = "a" Or z = "e" Or z = "i" Or z = "o" Or z = "u" Then y = MsgBox("Vowel",, "Display") Else MsgBox("Not Vowel") Quiz Programme Controls: Button, TextBox1 (to enter Name), TextBox2 (to enter Class) Public Class Student Private Sub Button1_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Form2.Show() Me.Hide() Form5.Label1.Text = TextBox1.Text Form5.Label2.Text = TextBox2.Text Controls: Timer, ProgressBar, Label Public Class Form2 Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick ProgressBar1.Value = ProgressBar1.Value + 1 If ProgressBar1.Value = 10 Then Label1.Text = "Loading..."

7 ElseIf ProgressBar1.Value = 20 Then Label1.Text = "Loading..." ElseIf ProgressBar1.Value = 30 Then Label1.Text = "Loading..." ElseIf ProgressBar1.Value = 40 Then Label1.Text = "Initializing..." ElseIf ProgressBar1.Value = 70 Then Label1.Text = "Please wait..." ElseIf ProgressBar1.Value = 80 Then Label1.Text = "Please wait..." ElseIf ProgressBar1.Value = 90 Then Label1.Text = "Please wait..." ElseIf ProgressBar1.Value = 100 Then Label1.Text = "Successful" Timer1.Enabled = False Form3.Show() Me.Hide() Controls: TextBox, Button Public Class Form3 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click If TextBox1.Text = "Ram Nath Kovind" Then Form5.Label3.Text = Val(Form5.Label3.Text) + 1 Form4.Show() Me.Hide() Controls: TextBox, Button Public Class Form4 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click If TextBox1.Text = "Venkaiah Naidu" Then Form5.Label3.Text = Val(Form5.Label3.Text) + 1 Form5.Show() Me.Hide() Controls: Button, Label1 (to display Name), Label2 (to display Class), Label3 (to display Mark), Label4 (to dispaly No of questions) Public Class Form5 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click MsgBox("Thank you") Me.Hide()

8 Online Shoppping List Controls: Label, Button, ListBox, CheckedListBox Public Class ShoppingList Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Label1.Text = Now() Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim i As Byte Dim code() As Integer = {101, 102, 103, 104, 105} Dim price() As Integer = {4500, 2400, 1200, 200, 250} ListBox1.Items.Clear() For i = 0 To CheckedListBox1.Items.Count - 1 If CheckedListBox1.GetItemCheckState(i) = CheckState.Checked Then ListBox1.Items.Add(code(i).ToString & " " & CheckedListBox1.Items(i) & " " & price(i).tostring) KeyPress (only letters are allowed in the TextBox) Controls: TextBox Public Class KeyPress Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress Select Case e.keychar Case ChrW(65) To ChrW(90), ChrW(97) To ChrW(122) Case Else e.handled = True MsgBox("Only letters allowed") End Select Sorting Controls: ListBox, Button1 (to add items into the ListBox), Button2 (to sort the items) Public Class Sorting Private Sub SortBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SortBtn.Click Dim arr(listbox1.items.count - 1), t, j As Integer For i As Integer = 0 To ListBox1.Items.Count - 1 arr(i) = ListBox1.Items(i) For i = 0 To ListBox1.Items.Count - 2 For j = i + 1 To ListBox1.Items.Count - 1

9 If arr(i) > arr(j) Then t = arr(i) arr(i) = arr(j) arr(j) = t ListBox1.Items.Clear() ListBox1.Items.AddRange(arr.Cast(Of Object).ToArray()) Private Sub AddItemBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AddItemBtn.Click Dim i, n As Integer ListBox1.Items.Clear() n = InputBox("How many numbers?") For i = 0 To n - 1 ListBox1.Items.Add(InputBox("Enter the number")) Display Capital of the Country selected in a ComboBox Controls: ComboBox, TextBox Public Class Capital Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged Select Case ComboBox1.SelectedIndex Case 0 TextBox1.Text = "Kabul" Case 1 TextBox1.Text = "Dhaka" Case 2 TextBox1.Text = "Timbu" Case 3 TextBox1.Text = "Bejing" Case 4 TextBox1.Text = "New Delhi" Case 5 TextBox1.Text = "Rangoon" Case 6 TextBox1.Text = "Kadmandu" Case 7 TextBox1.Text = "Islamabad" Case 8 TextBox1.Text = "Colombo" End Select Using OpenFileDialog, SaveFileDialog and FontDialog Controls: FontDialog, OpenFileDialog, SaveFileDialog, RichTextBox, Save button, Open button, Font button

10 Public Class DialogBoxes Private Sub FontBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FontBtn.Click If FontDialog1.ShowDialog <> Windows.Forms.DialogResult.Cancel Then RichTextBox1.ForeColor = FontDialog1.Color RichTextBox1.Font = FontDialog1.Font Private Sub SaveBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveBtn.Click SaveFileDialog1.Filter = "TXT Files (*.txt) *.txt" If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then My.Computer.FileSystem.WriteAllText(SaveFileDialog1.FileName, RichTextBox1.Text, True) Private Sub OpenBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OpenBtn.Click If OpenFileDialog1.ShowDialog <> Windows.Forms.DialogResult.Cancel Then RichTextBox1.LoadFile(OpenFileDialog1.FileName, RichTextBoxStreamType.PlainText) Text Editor Public Class TextEditor Private Sub SaveToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveToolStripMenuItem.Click If SaveFileDialog1.ShowDialog = Windows.Forms.DialogResult.OK Then RichTextBox1.SaveFile(SaveFileDialog1.FileName, RichTextBoxStreamType.PlainText) Private Sub ExitToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExitToolStripMenuItem.Click Me.Close() Private Sub CutToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CutToolStripMenuItem.Click RichTextBox1.Cut() Private Sub CopyToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CopyToolStripMenuItem.Click RichTextBox1.Copy() Private Sub PasteToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles PasteToolStripMenuItem.Click RichTextBox1.Paste()

11 Stop Watch Controls:Timer, Label, Start button, Stop button, Reset button Public Class Timer Private Sub StartBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles StartBtn.Click Timer1.Start() Me.stopwatch.Start() Private Sub StopBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles StopBtn.Click Timer1.Stop() Me.stopwatch.Stop() Private Sub ResetBtn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click Me.stopwatch.Reset() Label5.Text = "00:00:00:000" ListBox1.Items.Clear() Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick Dim elapsed As TimeSpan = Me.stopwatch.Elapsed Label5.Text = String.Format("{0:00}:{1:00}:{2:00}:{3:00}", Math.Floor(elapsed.TotalHours), elapsed.minutes, elapsed.seconds, elapsed.milliseconds)