Step 10: Write Code for Additional Buttons and a Check Box

  • Article

Now you're ready to complete the other four methods. You could copy and paste this code, but if you want to learn the most from this tutorial, type the code and use IntelliSense.

link to videoFor a video version of this topic, see Tutorial 1: Create a Picture Viewer in Visual Basic - Video 5 or Tutorial 1: Create a Picture Viewer in C# - Video 5.

Note

As a best practice: Always comment your code. Comments are information for a person to read, and it's worth the time to make your code understandable. Everything on a comment line is ignored by the program. In Visual C#, you comment a line by typing two forward slashes at the beginning (//), and in Visual Basic you comment a line by starting with a single quotation mark (').

To write code for additional buttons and a check box

  • Add the following code.

    Private Sub clearButton_Click() Handles clearButton.Click
    ' Clear the picture.
    PictureBox1.Image = Nothing
End Sub

Private Sub backgroundButton_Click() Handles backgroundButton.Click
    ' Show the color dialog box. If the user clicks OK, change the
    ' PictureBox control's background to the color the user chose.
    If ColorDialog1.ShowDialog() = DialogResult.OK Then
        PictureBox1.BackColor = ColorDialog1.Color
    End If
End Sub

Private Sub closeButton_Click() Handles closeButton.Click
    ' Close the form.
    Close()
End Sub

Private Sub CheckBox1_CheckedChanged() Handles CheckBox1.CheckedChanged
    ' If the user selects the Stretch check box, change 
    ' the PictureBox's SizeMode property to "Stretch". If the user 
    ' clears the check box, change it to "Normal".
    If CheckBox1.Checked Then
        PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage
    Else
        PictureBox1.SizeMode = PictureBoxSizeMode.Normal
    End If
End Sub

    private void clearButton_Click(object sender, EventArgs e)
{
    // Clear the picture.
    pictureBox1.Image = null;
}

private void backgroundButton_Click(object sender, EventArgs e)
{
    // Show the color dialog box. If the user clicks OK, change the
    // PictureBox control's background to the color the user chose.
    if (colorDialog1.ShowDialog() == DialogResult.OK)
        pictureBox1.BackColor = colorDialog1.Color;
}

private void closeButton_Click(object sender, EventArgs e)
{
    // Close the form.
    this.Close();
}

private void checkBox1_CheckedChanged(object sender, EventArgs e)
{
    // If the user selects the Stretch check box, 
    // change the PictureBox's
    // SizeMode property to "Stretch". If the user clears 
    // the check box, change it to "Normal".
    if (checkBox1.Checked)
        pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;
    else
        pictureBox1.SizeMode = PictureBoxSizeMode.Normal;
}

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