VB.NET Student Management Application: Code Walkthrough and Data Handling

VB.NET Student Management Application

Module Module1

Data Structure and Global Variables

Structure alu

Dim Codice As String(5)

Dim nominativo As String(25)

Dim Classe As String(5)

Dim Media As Single

End Structure

Public recalu As alu

Public numerec, pos, pos2, posgiusta, tot As Short

Public media As Single

Public classe As Short

Public recalu2 As alu

End Module

Frm9 – Student List by Name Ending

Student list of the class and name ending with

Public Class Frmvisua5

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

Txtvisua.Text = "iis6naudi" + Chr(13) + Chr(10)

Txtvisua.Text = Txtvisua.Text + "Student list of the class and name ending with " + txtnomi.Text + " " + txtclasse.Text + Chr(13) + Chr(10) + "Code Name Class Average " + Chr(13) + Chr(10)

Tot = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

If Microsoft.VisualBasic.Right(Trim(.nominativo), 2) = Trim(txtnomi.Text) And (Trim(.classe)) Then

Txtvisua.Text = Txtvisua.Text + .codice

End If

End With

Loop

End Sub

Private Sub Frmvisua5_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Read, , Len(recalu))

Pos = 0

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

End Class

Frm8 – Student Display by Initial Letter

Display of students with a name starting with 1 letter

Public Class Frmlettera

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

Txtvisua.Text = "iiss einaudi" + Chr(13) + Chr(10) + " Code Name Class Average " + Chr(13) + Chr(10)

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

If Microsoft.VisualBasic.Left(.nominativo, 1) = Trim(txtini.Text) Then

Txtvisua.Text = Txtvisua.Text + .codice + " " + .nominativo + " " + .classe + " " + CStr(.media) + Chr(13) + Chr(10)

End If

End With

Loop

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

End Class

Frm7 – Data Modification

DATA MODIFICATION MANAGEMENT

Public Class Frmmodi

Private Sub Btncerca_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btncerca.Click

Pos = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

.codice = Trim(txtcod.Text)

.nominativo = Trim(txtnomi.Text)

.classe = Trim(txtclasse.Text)

.media = Val(txtmedia.Text)

Pos = posgiusta

End With

Loop

End Sub

Private Sub Btnmodi_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnmodi.Click

With Recalu

.codice = Trim(txtcod.Text)

.nominativo = Trim(txtnomi.Text)

.classe = Trim(txtclasse.Text)

.media = Val(txtmedia.Text)

FilePut(1, recalu, posgiusta)

End With

End Sub

Private Sub Frmmodi_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.ReadWrite, , Len(recalu))

Pos = 0

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose(1)

Me.Hide()

Frmprinc.Show()

End Sub

End Class

Frm6 – Record Deletion

Public Class Frmcanc

Private Sub Btncancella_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btncancella.Click

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Read, , Len(recalu))

FileOpen(2, "alu2.dat", OpenMode.Random, OpenAccess.Write, , Len(recalu))

Pos = 0

Pos2 = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

If Trim(recalu.codice) <> Trim(txtcod.Text) Then

Recalu2 = recalu

Pos2 = Pos2 + 1

FilePut(2, recalu2, Pos2)

End If

Loop

FileClose()

Kill("alu.dat")

My.Computer.FileSystem.RenameFile("alu2.dat", "alu.dat")

End Sub

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Read, , Len(recalu))

Txtvisua.Text = "iis6naudi" + Chr(13) + Chr(10) + "Code Name Class Average " + Chr(13) + Chr(10)

Pos = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

Txtvisua.Text = Txtvisua.Text + .codice + " " + .nominativo + " " + .classe + " " + CStr(.media) + Chr(13) + Chr(10)

End With

Loop

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

End Class

Frm5 – Display by Average Range

Public Class Frmvisua3

Private Sub Frmvisua3_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileOpen(1, "alu.dat ", OpenMode.Random, OpenAccess.Read, , Len(recalu))

Pos = 0

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

Txtvisua.Text = "iis6naudi" + Chr(13) + Chr(10) + "display students with average >= and <= of" + Chr(13) + Chr(10) + "Code Name Class Average " + Chr(13) + Chr(10)

Tot = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

If (media >= Val(txtmin.Text)) And (media <= Val(txtmax.Text)) Then

Txtvisua.Text = Txtvisua.Text + .codice + " " + .nominativo + " " + CStr(.media) + " " + .classe

Tot = Tot + 1

End If

End With

Loop

Txtvisua.Text = Txtvisua.Text + "Total selected students: " + CStr(Tot)

End Sub

End Class

Frm4 – Students by Class

Public Class Frmvisua2

Private Sub Frmvisua2_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Read, , Len(recalu))

Pos = 0

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

Txtvisua.Text = " iis6naudi" + Chr(13) + Chr(10) + "display students by class" + Chr(13) + Chr(10) + "Code Name Class Average " + Chr(13) + Chr(10)

Tot = 0

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

If Trim(.classe) = Trim(lstclasse.Text) Then

Txtvisua.Text = Txtvisua.Text + .codice + " " + .nominativo + " " + CStr(.media) + " " + .classe + Chr(13) + Chr(10)

Tot = Tot + 1

End If

End With

Loop

Txtvisua.Text = Txtvisua.Text + "Total selected students " + CStr(Tot)

End Sub

End Class

Frm3 – Total Visualization

Public Class Frmvisuatot

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

Private Sub Btnvisua_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btnvisua.Click

Txtvisua.Text = "Code Name Class Average " + Chr(13) + Chr(10)

Do While Not Eof(1)

Pos = Pos + 1

FileGet(1, recalu, Pos)

With recalu

Txtvisua.Text = Txtvisua.Text + .codice + " " + .nominativo + " " + .classe + " " + CStr(.media) + Chr(13) + Chr(10)

End With

Loop

End Sub

Private Sub Frmvisuatot_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileClose()

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Read, , Len(recalu))

Pos = 0

End Sub

End Class

Frm2 – Student Insertion

Public Class Frminse

Private Sub Frminse_Load(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles MyBase.Load

FileOpen(1, "alu.dat", OpenMode.Random, OpenAccess.Write, , Len(recalu))

Numerec = LOF(1) / Len(recalu)

Pos = Numerec

End Sub

Private Sub Btntorna_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btntorna.Click

FileClose()

Me.Hide()

Frmprinc.Show()

End Sub

Private Sub Btninse_click(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Btninse.Click

Pos = Pos + 1

With recalu

.codice = Trim(txtcod.Text)

.nominativo = Trim(txtnom.Text)

.classe = Trim(lstclasse.Text)

.media = Trim(txtmedie.Text)

End With

FilePut(1, recalu, Pos)

Txtcod.Text = ""

Txtnom.Text = ""

Lstclasse.Text = ""

Txtmedie.Text = ""

Txtcod.Focus()

End Sub

End Class

Frm1 – Main Form

Public Class Frmprinc

Private Sub Rdbinse_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbinse.CheckedChanged

Me.Hide()

Frminse.Show()

End Sub

Private Sub Rdbvisuatot_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbvisuatot.CheckedChanged

Me.Hide()

Frmvisuatot.Show()

End Sub

Private Sub Rdbvisua2_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbvisua2.CheckedChanged

Me.Hide()

Frmvisua2.Show()

End Sub

Private Sub Rdbvisua4_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbvisua4.CheckedChanged

Me.Hide()

Frmvisua3.Show()

End Sub

Private Sub Rdbmodi_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbmodi.CheckedChanged

Me.Hide()

Frmmodi.Show()

End Sub

Private Sub Rdbvisua5_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbvisua5.CheckedChanged

Me.Hide()

Frmvisua5.Show()

End Sub

Private Sub Rdbcanc_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdbcanc.CheckedChanged

Me.Hide()

Frmcanc.Show()

End Sub

Private Sub Rdblettera_CheckedChanged(ByVal Sender As System.Object, ByVal E As System.EventArgs) Handles Rdblettera.CheckedChanged

Me.Hide()

Frmlettera.Show()

End Sub

End Class