Why is my application telling me that my clipboard is empty when clearly it's not?

Question

Im trying to take a screenshot of my screen with a console application and then save it to my desktop but for some reason.. its telling me that my clipboard is empty when clearly its not.. If you check the code you can see that I press PrintScreen and when you do that it saves it to the clipboard.

using System;
using System.Drawing;
using System.Windows.Forms;

namespace ScreenshotConsole
{
    class Program
    {

        static void Main(string[] args)
        {
            screenshot();
            Console.WriteLine("Printescreened");
            saveScreenshot();
            Console.ReadLine();
        }


        static void screenshot()
        {
            SendKeys.SendWait("{PRTSC}");
        }

        static void saveScreenshot()
        {
            //string path;
            //path = "%AppData%\\Sys32.png"; // collection of paths
            //path = Environment.ExpandEnvironmentVariables(path);

            if (Clipboard.ContainsImage() == true)
            {
                Image image = (Image)Clipboard.GetDataObject().GetData(DataFormats.Bitmap);
                image.Save("image.jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);
            }
            else
            {
                Console.WriteLine("Clipboard empty.");
            }
        }
    }
}

Are you sure sending prtsc works? What happens when you try to paste in paint? — Scott Chamberlain, Sep 30 '16 at 02:11
I'm 100% sure it works, if I only call the printscreen method it printscreens and I can paste it in paint. — Goober S. Johnsson, Sep 30 '16 at 02:12
There are [better ways to capture a screenshot](http://stackoverflow.com/questions/1163761) than using the clipboard. — D Stanley, Sep 30 '16 at 02:31

WAKU · Accepted Answer · 2016-09-30T02:30:06.450

5

It will take some time to screenshot, so you shoud add a delay after pressing {PRTSC}:

static void screenshot()
{
    SendKeys.SendWait("{PRTSC}");
    Thread.Sleep(500);
}

UPDATE

OK, I figured it out, add STAThreadAttribute to your main method:

    [STAThread]
    static void Main(string[] args)
    {
        screenshot();
        Console.WriteLine("Printescreened");
        saveScreenshot();
        Console.ReadLine();
    }

MSDN says that:

The Clipboard class can only be used in threads set to single thread apartment (STA) mode. To use this class, ensure that your Main method is marked with the STAThreadAttribute attribute.

More detail

edited Sep 30 '16 at 02:30

answered Sep 30 '16 at 02:18

WAKU

290
3
17

@GooberS.Johnsson SEE UPDATE – WAKU Sep 30 '16 at 02:32
Nvm it saves to the directory where it runs from, how would I change that? – Goober S. Johnsson Sep 30 '16 at 02:37
The image will be saved in "current folder", which will be same as your EXE file by default. It's better to specify an absolute path: `image.Save(@"d:\image.jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);` – WAKU Sep 30 '16 at 02:38
How would I specify the path? – Goober S. Johnsson Sep 30 '16 at 02:41
Oh I should of thought of that! Thank you so much! – Goober S. Johnsson Sep 30 '16 at 02:41
Glad to help you:) – WAKU Sep 30 '16 at 02:42

Why is my application telling me that my clipboard is empty when clearly it's not?

1 Answers1

UPDATE