panel clear everything

问题

I would like to reset a panel to its initial state. For e.g., I set an image as background, I drew graphics on a part of the panel. I have to clear everything. How?

回答1:

You have to clear the panel first

panel1.Controls.Clear();

then call the initial form.

panel1.Controls.Add(orig_form);

回答2:

Use the following code to delete all graphics from the panel

panel1.Invalidate();

If there is something you need to add to panel's initial state then after you call invalidate you again have to set those things.

If the initial state of panels needs some graphics or data you can put that in panel's graphics event, so everytime invalidate is called your panel get the initial state with those items.

回答3:

Use the panel1.refresh(); command. It resets the panel to its initial state.

回答4:

That is the only solution that worked for me:

private void button3_Click(object sender, EventArgs e)//Clear button
        {
        using (g = Graphics.FromImage(bmp))
        {
           g.Clear(Color.Transparent);//you can choose another color for your background here.
           panel1.Invalidate();
        }
    }

回答5:

Here is a SO link that looks to do exactly what you want:

Resetting a winform's elements to initialized state (C#/.Net)

来源：https://stackoverflow.com/questions/5959069/panel-clear-everything