无边框Winform，边框为1px

Question

This might sound like a weird question but I have C# Winform that I set the FormBorderStyle to None. So far everything is good but I was wondering if there was a way to add like a 1px border on around my form ? I know I could do it by creating my own image but I was wondering if there was a more natural way of doing it. Thanks

Answer 1

I consider using an image, or creating unnecessary controls for something that is easily paintable using GDI+ a waste of resources.

I think the simplest solution is overriding the OnPaint method of your form and drawing the border yourself:

protected override void OnPaint(PaintEventArgs e)
{
    e.Graphics.DrawRectangle(Pens.Black, this.Bounds);
}

Of course, you may also use your own Pen with your own color and width.

Answer 2

Use padding 1;1;1;1 to your form and set a background color to your form, and put a panel to your form. Set white or other normal background color to the panel. And set dock in parent controller. The background color of the form will act as a border.

Answer 3

如何只将Panel （并设置它的边框）添加到表单中？

Answer 4

Thanks for the suggestions, I've decided to create 4 1px label and just toss on the edge on each side. That way: 1. They are minding their own business on the side rather than taking up the whole middle if you use use a groupbox or panel. 2. You are able to choose change your border color.

Answer 5

There is no more natural or non natural ways to do it. It depends on what you want.

If you put a background image on the form, you have to consider a fact that in order to be able to support resizable for you have to have resizable background images.

If you simply draw on the background with a Pen or Brush , you can support also resizable form, but you have to work more if you want to do something cool, instead with image it's easier.

You can embed some control inside the form and with color's of them make a feeling of the border. Like control, you can use Panel , as suggested in comment, can use GroupBox that creates thin broder arround, or something else.

Answer 6

I created this method, so you could easily set the borderposition, color and thickness.

private void customBackgroundPainter(PaintEventArgs e, int linethickness = 2, Color linecolor = new Color(), int offsetborder = 6)
{
    Rectangle rect = new Rectangle(offsetborder, offsetborder, this.ClientSize.Width - (offsetborder * 2), this.ClientSize.Height - (offsetborder * 2));

    Pen pen = new Pen(new Color());
    pen.Width = linethickness;
    if (linecolor != new Color())
    {
        pen.Color = linecolor;
    }
    else
    {
        pen.Color = Color.Black;
    }

    e.Graphics.DrawRectangle(pen, rect);
}

You could use it in the OnPaintBackground likes this:

protected override void OnPaintBackground(PaintEventArgs e)
{
    base.OnPaintBackground(e);
    customBackgroundPainter(
    e,
    linethickness: 3,
    linecolor: Color.DarkOrange,
    offsetborder: 5
    );
}