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c# - Saving images from a WebBrowser Control

The following code runs, but the Bitmap generated is shifted down about half an inch and cutoff at the bottom. I checked the image width and height and it is creating an image of the correct size, just the image contents are shifted down and cutoff. I'm stumped... any ideas?

    using mshtml;
    using System.Drawing;
    using System.Runtime.InteropServices;

    [ComImport, InterfaceType((short)1), Guid("3050F669-98B5-11CF-BB82-00AA00BDCE0B")]
    private interface IHTMLElementRenderFixed
    {
        void DrawToDC(IntPtr hdc);
        void SetDocumentPrinter(string bstrPrinterName, IntPtr hdc);
    }

    public Bitmap GetImage(string id)
    {
        HtmlElement e = webBrowser1.Document.GetElementById(id);
        IHTMLImgElement img = (IHTMLImgElement)e.DomElement;
        IHTMLElementRenderFixed render = (IHTMLElementRenderFixed)img;

        Bitmap bmp = new Bitmap(img.width, img.height);
        Graphics g = Graphics.FromImage(bmp);
        IntPtr hdc = g.GetHdc();
        render.DrawToDC(hdc);
        g.ReleaseHdc(hdc);

        return bmp;
    }
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What you are doing is rendering the image as it is rendered by the browser with all the styles. I don't know if this is what your realy want? If you only want to download the image then it is easier to solve it with a web request as described in hte other answers.

If you realy want to render than the first step is to change

Bitmap bmp = new Bitmap(img.width, img.height);

to

Bitmap bmp = new Bitmap(e.OffsetRectangle.Width, e.OffsetRectangle.Height);

Now you get the complete rendered web browser image.

If you want a perfect solution even for big images you also have to scroll around and get the image tile by tile.


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