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In this article I will explain you how to drawing Text in GDI+.

Drawing Text

This section briefly discusses the drawing of text.

The DrawString method draws a text string on a graphics surface. It has many overloaded forms. Drawstring takes arguments that identify the text, font, brush, starting location, and string format.

Listing 3.6 uses the DrawString method to draw "Hello GDI+ World!" on a form.

LISTING 3.6: Drawing text

    Private Sub Form1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
        e.Graphics.DrawString("Hello GDI+ World!", New Font("Verdana", 16), New SolidBrush(Color.Red), New Point(20, 20))    End Sub

Note: You might notice in Listing 3.6 that we create Font, SolidBrush, and Point objects directly as parameters of the DrawString method. This method of creating objects means that we can't dispose of these objects, so some cleanup is left for the garbage collector.

Figure 3.7 shows the output from Listing 3.6




FIGURE 3.7: Drawing text

Now let's see another example of drawing text- this time using the StringFormat class, which defines the text format. Using StringFormat, you can set flags, alignment, trimming, and other options for the text. Listing 3.7 shows different ways to draw text on a graphics surface. In this example the FormatFlags property is set to StringFormatFlags.DirectionVertical, which draws a vertical text.

LISTING 3.7: Using DrawString to draw text on a graphics surface

    Private Sub Form1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
        ' create brushes
        Dim blueBrush As New SolidBrush(Color.Blue)
        Dim redBrush As New SolidBrush(Color.Red)
        Dim greenBrush As New SolidBrush(Color.Green)
        ' Create a rectangle
        Dim rect As New Rectangle(20, 20, 200, 100)

        ' The text to be drawn
        Dim DrawString As [String] = "Hello GDI+ World!"

        ' Create a Font object
        Dim DrawFont As New Font("Verdana", 14)
        Dim x As Single = 100.0F
        Dim y As Single = 100.0F
        Dim DrawFormat As New StringFormat()

        ' Set string format flag to direction vertical,
        ' which draws text vertically
        DrawFormat.FormatFlags = StringFormatFlags.DirectionVertical

        ' Draw string
        e.Graphics.DrawString("Drawing text", New Font("Tahoma", 14), greenBrush, rect)
        e.Graphics.DrawString(DrawString, New Font("Arial", 12), redBrush, 120, 140)
        e.Graphics.DrawString(DrawString, DrawFont, blueBrush, x, y, DrawFormat)

        ' Dispose of objects
        blueBrush.Dispose()
        redBrush.Dispose()
        greenBrush.Dispose()
        DrawFont.Dispose()
    End Sub

Figure 3.8 shows the output from Listing 3.7



FIGURE 3.8: Drawing text with different directions

Conclusion

Hope the article would have helped you in understanding drawing Text in GDI+. Read other articles on GDI+ on the website.