如何从 TWebBrowser 获取图像到 TImage

Question

I have a panel at the top of a form with a smallish TMemo set up as a drop target for URLs. Below that I have a Page Control with 2 tabs. I set up a TWebBrowser in one tab and some other stuff in the second tab. In the TWebBrowser, I need to login to a bug ticketing site we have, then browse tickets. Certain tickets have links to small images that clients want us to use (think something like logos). I can left-click on them and then drag-n-drop the link from the TWebBrowser to the TMemo at the top of the form. That picks up the image's URL and Title as expected.

The associated OnDrop event also switches to the 2nd tab and where I click a "Process" button. That causes the browser to navigate to the image (via Navigate2), which it loads into the browser window. That image is all that's in the browser window at this point.

So now I need the code to grab the image and load it into a TImage on the 2nd tabsheet. FWIW, the original image is a PNG.

I'm able to get the height and width of the image from the target image, but I'm not getting the image itself to show up in the TImage most of the time. Sometimes, but mostly not. I can load PNGs into these image objects just fine, so I know it displays PNGs properly.

(Maybe there's a way to do a download the image directly, but I wasn't able to get that to work. The TWebBrowser is used to login to an internal bug ticketing system where the images are being provided, and I can access that site only if it's on the same form and I've logged in. Otherwise the DL loads an HTML login page instead of the image. If there's a way to do that in the current framework, I'm open to suggestions.)

I'm finding the image file on the web page using IHTMLElement2.getelementsByTagName('img') and grabbing the first one (since I know that's all there is on the web page).

  img := getFirstImage;
  Image1_frame.Height := img.height+2;
  Image1_frame.Width := img.width+2;
  rnd := img as IHTMLElementRender ;
  rnd.DrawToDC(Image1.Canvas.Handle);

Image1 is aligned to Client on a panel named Image1_frame. So I set the frame's H & W -- they get set ok.

But the image is usually not visible. It's just white.

I see that DrawToDC is deprecated, but I haven't found what to replace it with.

Answer 1

You can use this approach to auto login (if needed): Automated Log In (webBrowser)

Then you can use this to get the Image: Image from TWebBrowser to TPicture