C#转换HTML内容为Bitmap

话不多说，直接贴代码

绘图部分，其中html内容为一个公网链接或者本地虚拟路径

public static Bitmap ConverHTML(string htmPath)
{
    string ImagePath = string.Empty;
    WebBrowser web = new WebBrowser();
    web.Navigate(htmPath);
    while (web.ReadyState != WebBrowserReadyState.Complete)
    {
        Application.DoEvents();
    }
    //矩形容器宽高
    Rectangle screen = Screen.PrimaryScreen.Bounds;
    screen.Width = (int)(screen.Width * 0.55);  //自定义55%宽
    screen.Height = (int)(screen.Height * 0.3); //30%高
    Size? imgsize = null;
    //设置宽高
    web.Width = screen.Width;
    web.Height = screen.Height;
    web.ScriptErrorsSuppressed = true;
    web.ScrollBarsEnabled = false;
    Rectangle body = web.Document.Body.ScrollRectangle;

    Rectangle docRectangle = new Rectangle()
    {
        Location = new Point(0, 0),
        Size = new Size(body.Width > screen.Width ? body.Width : screen.Width,
         body.Height > screen.Height ? body.Height : screen.Height)
    };
    Rectangle imgRectangle;
    if (imgsize == null)
        imgRectangle = docRectangle;
    else
        imgRectangle = new Rectangle()
        {
            Location = new Point(0, 0),
            Size = imgsize.Value
        };
    Bitmap bitmap = new Bitmap(web.Width, web.Height);
    IViewObject ivo = web.Document.DomDocument as IViewObject;

    using (Graphics g = Graphics.FromImage(bitmap))
    {
        IntPtr hdc = g.GetHdc();
        ivo.Draw(1, -1, IntPtr.Zero, IntPtr.Zero,
                 IntPtr.Zero, hdc, ref imgRectangle,
                 ref docRectangle, IntPtr.Zero, 0);
        g.ReleaseHdc(hdc);
    }
    return bitmap;
}

调用com组件用来实例化操作系统窗体

[ComVisible(true), ComImport()]
[GuidAttribute("0000010d-0000-0000-C000-000000000046")]
[InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
public interface IViewObject
{
	[return: MarshalAs(UnmanagedType.I4)]
        [PreserveSig]
        int Draw(
            [MarshalAs(UnmanagedType.U4)] UInt32 dwDrawAspect,
            int lindex,
            IntPtr pvAspect,
            [In] IntPtr ptd,
            IntPtr hdcTargetDev,
            IntPtr hdcDraw,
            [MarshalAs(UnmanagedType.Struct)] ref Rectangle lprcBounds,
            [MarshalAs(UnmanagedType.Struct)] ref Rectangle lprcWBounds,
            IntPtr pfnContinue,
            [MarshalAs(UnmanagedType.U4)] UInt32 dwContinue);
}