/// <summary>
/// Starts a task that waits for the next rendering from Chrome.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="ignoreExistingScreenshot">Ignore existing bitmap (if any) and return the next avaliable bitmap</param>
/// /// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Task<Bitmap>.</returns>
public Task <Bitmap> ScreenshotAsync(bool ignoreExistingScreenshot = false, PopupBlending blend = PopupBlending.Main)
{
// Try our luck and see if there is already a screenshot, to save us creating a new thread for nothing.
var screenshot = ScreenshotOrNull(blend);
var completionSource = new AsyncTaskCompletionSource <Bitmap>();
if (screenshot == null || ignoreExistingScreenshot)
{
EventHandler <OnPaintEventArgs> paint = null; // otherwise we cannot reference ourselves in the anonymous method below
paint = (sender, e) =>
{
// Chromium has rendered. Tell the task about it.
Paint -= paint;
completionSource.TrySetResultAsync(ScreenshotOrNull());
};
Paint += paint;
}
else
{
completionSource.TrySetResultAsync(screenshot);
}
return(completionSource.Task);
}
/// <summary>
/// Immediately returns a copy of the last rendering from Chrome,
/// or null if no rendering has occurred yet.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Bitmap.</returns>
public Bitmap ScreenshotOrNull(PopupBlending blend = PopupBlending.Main)
{
lock (BitmapLock)
{
if (blend == PopupBlending.Main)
{
return(BitmapBuffer.CreateBitmap());
}
if (blend == PopupBlending.Popup)
{
return(PopupOpen ? PopupBuffer.CreateBitmap() : null);
}
var bitmap = BitmapBuffer.CreateBitmap();
if (PopupOpen && bitmap != null)
{
var popup = PopupBuffer.CreateBitmap();
if (popup == null)
{
return(bitmap);
}
return(MergeBitmaps(bitmap, popup));
}
return(bitmap);
}
}
/// <summary>
/// Immediately returns a copy of the last rendering from Chrome,
/// or null if no rendering has occurred yet.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Bitmap.</returns>
public Bitmap ScreenshotOrNull(PopupBlending blend = PopupBlending.Main)
{
lock (BitmapLock)
{
if (blend == PopupBlending.Blend)
{
if (PopupOpen && Bitmap != null && Popup != null)
{
return(MergeBitmaps(Bitmap, Popup));
}
return(Bitmap == null ? null : new Bitmap(Bitmap));
}
else if (blend == PopupBlending.Popup)
{
if (PopupOpen)
{
return(Popup == null ? null : new Bitmap(Popup));
}
return(null);
}
return(Bitmap == null ? null : new Bitmap(Bitmap));
}
}
/// <summary>
/// Immediately returns a copy of the last rendering from Chrome,
/// or null if no rendering has occurred yet.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Bitmap.</returns>
public Bitmap ScreenshotOrNull(PopupBlending blend = PopupBlending.Main)
{
if (RenderHandler == null)
{
throw new NullReferenceException("RenderHandler cannot be null. Use DefaultRenderHandler unless implementing your own");
}
var renderHandler = RenderHandler as DefaultRenderHandler;
if (renderHandler == null)
{
throw new Exception("ScreenshotOrNull and ScreenshotAsync can only be used in combination with the DefaultRenderHandler");
}
lock (renderHandler.BitmapLock)
{
if (blend == PopupBlending.Main)
{
return(renderHandler.BitmapBuffer.CreateBitmap());
}
if (blend == PopupBlending.Popup)
{
return(renderHandler.PopupOpen ? renderHandler.PopupBuffer.CreateBitmap() : null);
}
var bitmap = renderHandler.BitmapBuffer.CreateBitmap();
if (renderHandler.PopupOpen && bitmap != null)
{
var popup = renderHandler.PopupBuffer.CreateBitmap();
if (popup == null)
{
return(bitmap);
}
return(MergeBitmaps(bitmap, popup, renderHandler.PopupPosition));
}
return(bitmap);
}
}
public Task <Bitmap> ScreenshotAsync(bool ignoreExistingScreenshot = false, PopupBlending blend = PopupBlending.Main)
{
ThrowExceptionIfDisposed();
// Try our luck and see if there is already a screenshot, to save us creating a new thread for nothing.
var screenshot = ScreenshotOrNull(blend);
var completionSource = new TaskCompletionSource <Bitmap>();
if (screenshot == null || ignoreExistingScreenshot)
{
EventHandler <OnPaintEventArgs> afterPaint = null; // otherwise we cannot reference ourselves in the anonymous method below
afterPaint = (sender, e) =>
{
// Chromium has rendered. Tell the task about it.
AfterPaint -= afterPaint;
//If the user handled the Paint event then we'll throw an exception here
//as it's not possible to use ScreenShotAsync as the buffer wasn't updated.
if (e.Handled)
{
completionSource.TrySetException(new InvalidOperationException("OnPaintEventArgs.Handled = true, unable to process request. The buffer has not been updated"));
}
else
{
completionSource.TrySetResultAsync(ScreenshotOrNull(blend));
}
};
AfterPaint += afterPaint;
}
else
{
completionSource.TrySetResultAsync(screenshot);
}
return(completionSource.Task);
}
/// <summary>
/// Immediately returns a copy of the last rendering from Chrome,
/// or null if no rendering has occurred yet.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Bitmap.</returns>
public Bitmap ScreenshotOrNull(PopupBlending blend = PopupBlending.Main)
{
lock (BitmapLock)
{
if (blend == PopupBlending.Blend)
{
if (PopupOpen && Bitmap != null && Popup != null)
{
return MergeBitmaps(Bitmap, Popup);
}
return Bitmap == null ? null : new Bitmap(Bitmap);
}
else if(blend == PopupBlending.Popup)
{
if (PopupOpen)
{
return Popup == null ? null : new Bitmap(Popup);
}
return null;
}
return Bitmap == null ? null : new Bitmap(Bitmap);
}
}
/// <summary>
/// Starts a task that waits for the next rendering from Chrome.
/// Chrome also renders the page loading, so if you want to see a complete rendering,
/// only start this task once your page is loaded (which you can detect via FrameLoadEnd
/// or your own heuristics based on evaluating JavaScript).
/// It is your responsibility to dispose the returned Bitmap.
/// The bitmap size is determined by the Size property set earlier.
/// </summary>
/// <param name="ignoreExistingScreenshot">Ignore existing bitmap (if any) and return the next avaliable bitmap</param>
/// /// <param name="blend">Choose which bitmap to retrieve, choose <see cref="PopupBlending.Blend"/> for a merged bitmap.</param>
/// <returns>Task<Bitmap>.</returns>
public Task<Bitmap> ScreenshotAsync(bool ignoreExistingScreenshot = false, PopupBlending blend = PopupBlending.Main)
{
// Try our luck and see if there is already a screenshot, to save us creating a new thread for nothing.
var screenshot = ScreenshotOrNull(blend);
var completionSource = new TaskCompletionSource<Bitmap>();
if (screenshot == null || ignoreExistingScreenshot)
{
EventHandler newScreenshot = null; // otherwise we cannot reference ourselves in the anonymous method below
newScreenshot = (sender, e) =>
{
// Chromium has rendered. Tell the task about it.
NewScreenshot -= newScreenshot;
completionSource.TrySetResultAsync(ScreenshotOrNull());
};
NewScreenshot += newScreenshot;
}
else
{
completionSource.TrySetResultAsync(screenshot);
}
return completionSource.Task;
}
