Create a Bitmap of a webpage programmatically...how?

[Joe Black]

Hi everyone,
I have a pesky little problem that is driving me nuts.
I'm trying to capture an image of a web page programmatically in a
background thread or process.
What I'd like to do is create a Bitmap object of a webpage from, say,
the new WebBrowser control of .net 2.0 or even the old ActiveX browser
control, without opening any forms.

I tried with the new WebBrowser control, but the only thing I've managed
to do is open up a form with the control in it, and do a screen capture
of a rectangle the same size of the control.
But the problem is that I need to do it /without/ opening the Form. :(
I think I'm getting close, but I really can't find a way to do it as a
background process.

Can anyone please point me in the right direction?

Thanks

--
Joe Black

[Bob Powell [MVP]]

Interop and the PrintWindow API.

--
Bob Powell [MVP]
Visual C#, System.Drawing

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"Joe Black" <jo*@black.com> wrote in message
news:DZ*******************@twister2.libero.it...

Hi everyone,
I have a pesky little problem that is driving me nuts.
I'm trying to capture an image of a web page programmatically in a
background thread or process.
What I'd like to do is create a Bitmap object of a webpage from, say, the
new WebBrowser control of .net 2.0 or even the old ActiveX browser
control, without opening any forms.

I tried with the new WebBrowser control, but the only thing I've managed
to do is open up a form with the control in it, and do a screen capture of
a rectangle the same size of the control.
But the problem is that I need to do it /without/ opening the Form. :(
I think I'm getting close, but I really can't find a way to do it as a
background process.

Can anyone please point me in the right direction?

Thanks

--
Joe Black

[Joe Black]

Thanks for your reply,
I tried with PrintWindow API, but all I get is a black bitmap if try to
capture a control that is not visible.

Here is what i do:

[DllImport("user32.dll")]
private static extern bool PrintWindow(IntPtr hwnd, IntPtr hdcBlt, uint
nFlags);

//...

Bitmap bm = new Bitmap(webBrowser1.Width, this.webBrowser1.Height);
Graphics g = Graphics.FromImage(bm);
IntPtr hdc = g.GetHdc();
Form1.PrintWindow(webBrowser1.Handle, hdc, 0);
g.ReleaseHdc(hdc);
g.Flush();
g.Dispose();
this.pictureBox1.Image = bm;

//...

Am I missing something?

--
Joe Black

Bob Powell [MVP] wrote on 12/04/2005 19.38:

Interop and the PrintWindow API.

[Lee Jackson]

On Tue, 12 Apr 2005 15:40:19 GMT, Joe Black <jo*@black.com> wrote:

Hi everyone,
I have a pesky little problem that is driving me nuts.
I'm trying to capture an image of a web page programmatically in a
background thread or process.
What I'd like to do is create a Bitmap object of a webpage from, say,
the new WebBrowser control of .net 2.0 or even the old ActiveX browser
control, without opening any forms.

I tried with the new WebBrowser control, but the only thing I've managed
to do is open up a form with the control in it, and do a screen capture
of a rectangle the same size of the control.
But the problem is that I need to do it /without/ opening the Form. :(
I think I'm getting close, but I really can't find a way to do it as a
background process.

Can anyone please point me in the right direction?

Thanks

I have exactly the same requirement coming at me somewhere down the
road - if you find a solution please let us know.

Ive not given this very much thought myself yet but one idea might be
to use something like virtual print driver
http://www.print-driver.com/... I REALLY dont know if a third party
component would be requied for this but just a thought.

Regards