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c# - Can I use Graphics object in any other event than Paint event?

I have a WinForm with a docked Panel. I overrode the Panel’s Paint event. I have a line that sets up _graphics object:

private Graphics _graphics;

In the override I initialize _graphics object:

private void GridPanel_Paint(object sender, PaintEventArgs e)
{
    _graphics = e.Graphics;

    <snip>
    …
    </snip>
}

Here comes the stupid part, Can I use this _graphics object in any other event like MouseMove?

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by (71.8m points)

It depends what do you mean by "use".

Graphics is disposable. After repainting, control disposes Graphics instance, that was passed into Paint event handler. From that point, disposed object is useless. But caching a reference to that instance is absolutely legal.


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