Database leaks or connection pools blocking subsequent runtime queries.
Imports System.Data.OleDb Public Class Form1 Dim conn As New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\Student\Documents\Database.accdb;") Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click Try conn.Open() Dim cmd As New OleDbCommand("INSERT INTO Students (Name, Age) VALUES ('" & txtName.Text & "', " & txtAge.Text & ")", conn) cmd.ExecuteNonQuery() MessageBox.Show("Record Saved Successfully!") Catch ex As Exception MessageBox.Show("Error: " & ex.Message) Finally conn.Close() End Try End Sub End Class Use code with caution. Part 2: VB.NET Lab Program Fixes & Debugging
Dim choice As Integer = Convert.ToInt32(Console.ReadLine()) vb net lab programs for bca students fix
: Convert the input to the correct data type.
Use the Debug.WriteLine() method to write diagnostic messages to the Output window during runtime without interrupting execution. This is invaluable for tracking program flow. Use the Debug
✅ Always use For...Next loops for a fixed number of iterations; it’s harder to mess up than Do While . 5. Input Validation: Crashing on Empty Boxes
To systematically any VB.NET lab program, students should follow this 5-step process: or Date .
BCA lab exams frequently require connecting a VB.NET form to a Microsoft Access ( .accdb ) or SQL Server database to Insert, Update, Delete, and View records. Common Student Errors
: Attempting to name the constructor function the same as the class (like in Java/C++). In VB.NET, constructors must always be named Sub New .
Try conn.Open() cmd.ExecuteNonQuery() MessageBox.Show("Student updated successfully!") Catch ex As Exception MessageBox.Show("Error: " & ex.Message) Finally conn.Close() End Try Else MessageBox.Show("Student not found!") End If End Sub
Syntax error in INSERT INTO statement when using fields like Password , User , or Date .