Visual Basic 2015 Lesson 27: Creating Rectangles

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In the in the preceding lesson , we have learned how to create Graphics and the Pen objects to draw straight lines in Visual Basic 2015 . Now we shall learn how to draw rectangles.

27.1 Creating Rectangle

To draw a rectangle on the default form in Visual Basic 2015, there are two ways:

(i)The first  is to draw a rectangle directly using the DrawRectangle method by specifying its upper-left corner’s coordinate and it width and height. You also need to create a Graphics and a Pen object to handle the actual drawing. The method of the Graphics object to draw the rectangle is DrawRectangle .The syntax is:

myGrapphics.DrawRectangle(myPen, X, Y, width, height)

Where myGraphics is the variable name of the Graphics object and myPen is the variable name of the Pen object created by you. You can use any valid and meaningful variable names. X, Y is the coordinate of the upper left corner of the rectangle while width and height are self-explanatory, i.e, the width and height of the rectangle.




The  code is as follows:

Dim myPen As Pen

myPen = New Pen(Drawing.Color.Blue, 5)

Dim myGraphics As Graphics = Me.CreateGraphics

myGraphics.DrawRectangle(myPen, 0, 0, 100, 50)

(ii) The second way is to create a rectangle object first and then draw this triangle using the DrawRectangle method. The syntax is as shown below:

myGraphics.DrawRectangle(myPen,myRectangle) where myRectangle is the rectangle object created by you, the user.

The code to create a rectangtle object is as shown below:

Dim myRectangle As New Rectangle

myRect.X = 10

myRect.Y = 10

myRect.Width = 100

myRect.Height = 50

You can also create a rectangle object using a one-line code as follows:

Dim myRectangle As New Rectangle(X,Y,width, height)

and the code to draw the above rectange is

myGraphics.DrawRectangle(myPen, myRectangle)



27.2 Customizing Line Style of the Pen Object

The shape we draw so far are drawn with solid line, we can actually customize the line style of the Pen object so that we have dotted line, line consisting of dashes and more. For example, the syntax to draw with dotted line is shown below:

myPen.DashStyle=Drawing.Drawing2D.DashStyle.Dot

Where the last argument Dot specifies a particular line DashStyle value, a line that makes up of dots here. Other DashStyles values are Dash, DashDot, DashDotDot and Solid.The following code draws a rectangle with blue dotted line.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickDim myPen As Pen

myPen = New Pen(Drawing.Color.Blue, 5)
Dim myGraphics As Graphics = Me.CreateGraphics
myPen.DashStyle = Drawing.Drawing2D.DashStyle.Dot
myGraphics.DrawRectangle(myPen, 10, 10, 100, 50)

End Sub

The output image is as  shown in Figure 27.1

vb2013_figure26.1

 Figure 27.1




If you change the DashStyle value to DashDotDot, you will get the following rectangle :

vb2013_figure26.2Figure 27.2

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