Lesson 27: Mastering Rectangle Drawing in VB2022

Private Sub BtnDrawRectangle_Click(sender As Object, e As EventArgs) Handles BtnDrawRectangle.Click
    ' Create graphics object
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create a blue pen for border
    Dim borderPen As New Pen(Color.Blue, 3)
    
    ' Create a red brush for fill
    Dim fillBrush As New SolidBrush(Color.Red)
    
    ' Define rectangle position and size
    Dim rect As New Rectangle(50, 50, 200, 150)
    
    ' Draw the rectangle border
    g.DrawRectangle(borderPen, rect)
    
    ' Fill the rectangle
    g.FillRectangle(fillBrush, rect)
    
    ' Clean up resources
    borderPen.Dispose()
    fillBrush.Dispose()
    g.Dispose()
End Sub

Private Sub BtnStyledRectangle_Click(sender As Object, e As EventArgs) Handles BtnStyledRectangle.Click
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create a custom pen
    Dim myPen As New Pen(Color.Purple, 4)
    myPen.DashStyle = Drawing.Drawing2D.DashStyle.DashDotDot
    
    ' Create gradient brush
    Dim gradBrush As New Drawing2D.LinearGradientBrush(
        New Point(50, 50),
        New Point(250, 200),
        Color.Yellow,
        Color.Orange)
    
    ' Define rectangle
    Dim rect As New Rectangle(50, 50, 200, 150)
    
    ' Draw filled rectangle
    g.FillRectangle(gradBrush, rect)
    
    ' Draw border
    g.DrawRectangle(myPen, rect)
    
    ' Clean up
    myPen.Dispose()
    gradBrush.Dispose()
    g.Dispose()
End Sub

Private Sub BtnRoundedRectangle_Click(sender As Object, e As EventArgs) Handles BtnRoundedRectangle.Click
    Dim g As Graphics = Me.CreateGraphics()
    
    ' Create pen and brush
    Dim myPen As New Pen(Color.DarkGreen, 3)
    Dim myBrush As New SolidBrush(Color.LightGreen)
    
    ' Define rectangle and corner radius
    Dim rect As New Rectangle(50, 50, 200, 120)
    Dim radius As Integer = 20
    
    ' Create rounded rectangle path
    Dim path As New Drawing2D.GraphicsPath()
    
    ' Calculate diameter
    Dim diameter As Integer = radius * 2
    
    ' Top-left corner
    path.AddArc(rect.X, rect.Y, diameter, diameter, 180, 90)
    
    ' Top-right corner
    path.AddArc(rect.X + rect.Width - diameter, rect.Y, diameter, diameter, 270, 90)
    
    ' Bottom-right corner
    path.AddArc(rect.X + rect.Width - diameter, rect.Y + rect.Height - diameter, diameter, diameter, 0, 90)
    
    ' Bottom-left corner
    path.AddArc(rect.X, rect.Y + rect.Height - diameter, diameter, diameter, 90, 90)
    
    ' Close path
    path.CloseFigure()
    
    ' Draw and fill the rounded rectangle
    g.FillPath(myBrush, path)
    g.DrawPath(myPen, path)
    
    ' Clean up
    myPen.Dispose()
    myBrush.Dispose()
    g.Dispose()
End Sub

Private Sub BtnRectangleGrid_Click(sender As Object, e As EventArgs) Handles BtnRectangleGrid.Click
    Dim g As Graphics = Me.CreateGraphics()
    Dim rand As New Random()
    
    ' Clear the form
    g.Clear(Me.BackColor)
    
    ' Draw 4x4 grid of rectangles
    For row As Integer = 0 To 3
        For col As Integer = 0 To 3
            Dim x As Integer = 30 + col * 100
            Dim y As Integer = 30 + row * 100
            Dim width As Integer = 80
            Dim height As Integer = 80
            
            ' Create random color
            Dim color As Color = Color.FromArgb(rand.Next(256), rand.Next(256), rand.Next(256))
            
            ' Create pen and brush
            Dim myPen As New Pen(Color.Black, 2)
            Dim myBrush As New SolidBrush(color)
            
            ' Create rectangle
            Dim rect As New Rectangle(x, y, width, height)
            
            ' Draw filled rectangle
            g.FillRectangle(myBrush, rect)
            
            ' Draw border
            g.DrawRectangle(myPen, rect)
            
            ' Clean up
            myPen.Dispose()
            myBrush.Dispose()
        Next
    Next
    
    g.Dispose()
End Sub