Using the InternetExplorer object, I'm able to print a web page. But when I try to print a file, I get the following error:
System.Runtime.InteropServices.COMException: The object invoked has disconnected from its clients.
What am I doing wrong?
Here's the code (thanks to this answer):
public class Program
{
static void main(string[] args)
{
// this works
(new HTMLPrinter()).Print("www.google.com");
// this brings up the file in a browser
// but then throws an exception when checking print status!
(new HTMLPrinter()).Print("C:\Temp\test.html");
}
}
public class HTMLPrinter
{
private bool documentLoaded;
private bool documentPrinted;
private void ie_DocumentComplete(object pDisp, ref object URL)
{
documentLoaded = true;
}
private void ie_PrintTemplateTeardown(object pDisp)
{
documentPrinted = true;
}
public void Print(string htmlFilename)
{
documentLoaded = false;
documentPrinted = false;
InternetExplorer ie = new InternetExplorerClass();
ie.DocumentComplete += new DWebBrowserEvents2_DocumentCompleteEventHandler(ie_DocumentComplete);
ie.PrintTemplateTeardown += new DWebBrowserEvents2_PrintTemplateTeardownEventHandler(ie_PrintTemplateTeardown);
object missing = Missing.Value;
ie.Navigate(htmlFilename, ref missing, ref missing, ref missing, ref missing);
// An exception is thrown at
// SHDocVw.InternetExplorerClass.QueryStatusWB
// only when trying to print a file!
// Exception details: System.Runtime.InteropServices.COMException:
// The object invoked has disconnected from its client.
while (!documentLoaded && ie.QueryStatusWB(OLECMDID.OLECMDID_PRINT) != OLECMDF.OLECMDF_ENABLED)
Thread.Sleep(100);
ie.ExecWB(OLECMDID.OLECMDID_PRINT, OLECMDEXECOPT.OLECMDEXECOPT_DONTPROMPTUSER, ref missing, ref missing);
while (!documentPrinted)
Thread.Sleep(100);
ie.DocumentComplete -= ie_DocumentComplete;
ie.PrintTemplateTeardown -= ie_PrintTemplateTeardown;
ie.Quit();
}
}
