Question

I have a Form that contains only 2 things, a PictureBox and a Label.

I added a mouse click event handler to the picture box.

this.pictureBox1.MouseClick += picture_MouseClick;

Inside the handler I need to check if the location of the mouse click is within the bounds of the label. To do this, I am using the mouse event location and checking to see whether that location is within the bounds of the label.

private void picture_MouseClick(object sender, MouseEventArgs e)
{
    if (label1.Bounds.Contains(e.Location))
    {
        MessageBox.Show("FOUND YOU!");
    }
}

I expected this to work as it seems easy enough however the click location (the orange box in the image) that leads to the MessageBox being shown is offset down and to the right of the label.

Is this because the mouse event is relative to the PictureBox and the Label bounds are relative to the Form? Or vice versa?

By the way, the label you see in the image is hidden at runtime. I am just using the label as a “hack” way of knowing if the user clicked in a certain spot.

public Form1()
{
    InitializeComponent();
    this.label1.Visible = false;
    this.pictureBox1.MouseClick += picture_MouseClick;
}

(I tried subtracting the width of the label from e.X and the height of the label from e.Y but that didn’t seem to work.)

Thank you,

Jan

Answer 1

The e.Location is the mouse position (a point) relative to the upper-left corner of the picturebox.
The Bounds property is relative to the container of the control.
(And in this case, the container is the form, as you and SLacks have rightly pointed out)

To check the correct position I will try with this code (now tested)

Point p = e.Location;
p.X += pictureBox1.Left;
p.Y += pictureBox1.Top;
if(label1.Bounds.Contains(p))
   .....