private static Task WaitForBrowserLoadingAsync(OffscreenBrowser browser)
{
var tcs = new TaskCompletionSource <bool>();
LoadingStateChangeDelegate handler = null;
handler = (cefBrowser, loading, back, forward) => {
if (loading)
{
return;
}
browser.LoadingStateChanged -= handler;
tcs.TrySetResult(true);
};
browser.LoadingStateChanged += handler;
return(tcs.Task);
}
public static async Task <int> TakeScreenshotAsync(string url, int width, int height, string[] args)
{
try {
var mainArgs = new CefMainArgs(args);
// create app
var app = new OffscreenApp();
var exitCode = CefRuntime.ExecuteProcess(mainArgs, app, IntPtr.Zero);
if (exitCode != -1)
{
return(exitCode);
}
// init CEF
var settings = new CefSettings {
SingleProcess = false,
MultiThreadedMessageLoop = true,
LogSeverity = CefLogSeverity.Error,
LogFile = "CefGlue.log"
};
CefRuntime.Initialize(mainArgs, settings, app, IntPtr.Zero);
// create browser
var browser = new OffscreenBrowser(url, width, height);
// wait for the site to be loaded
await WaitForBrowserLoadingAsync(browser).ConfigureAwait(false);
await Task.Delay(1000).ConfigureAwait(false);
browser.WindowBitmap.Save("output.png");
// dispose everything
var host = browser.GetBrowser().GetHost();
host.CloseBrowser();
host.Dispose();
CefRuntime.Shutdown();
return(0);
} catch (Exception exc) {
Console.WriteLine(exc.Message);
}
return(-1);
}
