Visual Basic .NET (VB.NET) remains a staple in many BCA curricula due to its rapid application development (RAD) capabilities and gentle learning curve. However, "It compiles on my machine" rarely survives the lab evaluator’s test data.
: A Windows Form application with textboxes for two numbers and buttons for addition, subtraction, multiplication, and division.
Try ' The code that might cause an exception Dim result As Integer = 10 / numberFromUser Catch ex As Exception ' Code that runs if an exception occurs MessageBox.Show("An error occurred: " & ex.Message) Finally ' Code that ALWAYS runs, whether there was an error or not ' Good for closing files or database connections End Try vb net lab programs for bca students fix
Public Class CalculatorForm Private Sub btnPlus_Click(sender As Object, e As EventArgs) Handles btnPlus.Click Dim num1 As Double = Convert.ToDouble(txtNum1.Text) Dim num2 As Double = Convert.ToDouble(txtNum2.Text) txtResult.Text = (num1 + num2).ToString() End Sub Private Sub btnDiv_Click(sender As Object, e As EventArgs) Handles btnDiv.Click Dim num1 As Double = Convert.ToDouble(txtNum1.Text) Dim num2 As Double = Convert.ToDouble(txtNum2.Text) If num2 = 0 Then MessageBox.Show("Divide by zero error!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error) txtResult.Text = "Undefined" Else txtResult.Text = (num1 / num2).ToString() End If End Class End Class Use code with caution. Common Error & Fix
: Always document your code with comments, maintain proper indentation, and test edge cases (negative numbers, empty inputs, large values). A well-tested program is better than a feature-rich buggy one. Visual Basic
: Create a form that intentionally triggers and handles:
: MenuStrip , RichTextBox , OpenFileDialog , SaveFileDialog . Try ' The code that might cause an
Now, let's apply our tools to the specific types of programs you'll encounter in the BCA .NET lab.
: A program to convert Fahrenheit to Celsius and vice-versa using a simple formula.
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