c# - .NET Custom UserControl 的内容在调整父级大小时消失

Question

我派生了 .NET UserControl，以制作我自己的 PictureList 类。但是，当我调整控件的父级大小时，控件的内容消失了。没有发出 Resize 事件或其他任何事件。我遗漏了与问题无关的代码。

    public ImageList(int width, int height)
    {
        ClientSize = new Size(width, height);
        ResizeRedraw = true;

    }


    // Ensure background transparency will be handled corretly.
    protected override CreateParams CreateParams
    {
        get {
            CreateParams cp = base.CreateParams;
            cp.ExStyle |= 0x20; // WS_EX_TRANSPARENT
            return cp;
        }
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        MessageBox.Show("This messagebox is only shown upon the first drawing, but not after the magically disappearing of the contents");

        img = /*the image to draw*/
        rect = /*the size of the image*/
        e.Graphics.DrawImage(img, rect);
    }

Answer 1

是否需要启用AutoRedraw？