Sending data from one application to another application file

Question

Hi,
I am developing an application from where i have to send data to another application which is made by Magtek for encoding data in swipe card. I want to know is it possible to send the data to an exe which is already exist, that exe is having few textbox don't know the name of the textbox as well. Or is there any other so that i can send data to that exe file. Please help!!!!!!!!!! :)

Vulpes · Answer

As the timer's Elapsed event is called on a background thread, you need to marshal any code which accesses controls back to the UI thread. To do that, this code: label1.Text = text; Regex rex = new Regex(@"\d+"); Match mm = rex.Match(label10.Text); if (mm.Success) { label1.Text = "$ " + mm.Value; } needs to be wrapped as follows: this.Invoke(new MethodInvoker(delegate() { label1.Text = text; Regex rex = new Regex(@"\d+"); Match mm = rex.Match(label10.Text); if (mm.Success) { label1.Text = "$ " + mm.Value; } }));

Vulpes · Answer

Sending information in the reverse direction is a bit trickier. What I'd suggest is that you: 1. Tab down to the textbox you want to read or, if it has a shortcut key, send it Alt + key. 2. To make sure it's selected, send it the HOME key and then SHIFT + END 3. Send it CTRL + C to copy the selected text to the clipboard 4. Use Clipboard.GetText from your application to read the text from the clipboard. The code to do steps 2 to 4 will be something like this: procs[0].WaitForInputIdle(); SendKeys.Send("{HOME}"); SendKeys.Send("+{END}"); SendKeys.Send("^C"); procs[0].WaitForInputIdle(); string text = Clipboard.GetText();

Sam Hobbs · Answer

The problem with SendKeys is that you need to ensure the control has focus and there are other details that are often more work than we realize initially. A better solution is to get the controls (textbox or whatever) and put the text into them directly. For clicking a button, the best solution usually is to send a BN_CLICKED to the parent (form). It is usually possible to get the control id for controls such as textboxes and buttons using Spy++, which is a tool in C++ tools. You can probably get the control ids and they will always be the same everytime the application (Magtek) executes. So then you can get the window handle of the controls and send messages to them. There are many details about doing that. So for now please at least look for Spy++. In the Start menu go to Visual Studio and in that look for Visual Studio Tools. Look there for Spy++. If you do not find it there then look in other menus such as Windows SDK Tools. For me the executabloe is at: "C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\Tools\spyxx.exe" Oh, I almost forgot; silly me. Spy++ should be in the Tools menu in VS. Learn how to use that. In the toolbar is a "Find Window" tool; actually two of them and I don't know the difference. The icon is binoculars. Using that, you can drag to the Magtek window to explore it. Let me know when you have done that much. Note that in a previous message Vulpes said: There is a way to send text directly to another application's textbox using the Win32 API but you need to know the textbox's name so that you can get its window handle. Frankly, it's a bit of a 'hit and miss' affair even if you have all the info available! However I think it is easier and more reliable than that indicates. I know it is and I have seen questions such as this many times. I consider the technique of sending text directly to a textbox to be more reliable based on other threads I have seen in the CodeGuru VC forum. The SendKeys solution often has timing issues that is rarely a problem the other way.

Vulpes · Answer

If the 3 textboxes receive focus one after the other, then I'd try sending the TAB key between each piece of text: private void button1_Click(object sender, EventArgs e) { string textToSend = "The quick brown fox"; string textToSend2 = "jumped over"; string textToSend3 = "the lazy dog"; Process[] procs = Process.GetProcessesByName("WindowsFormsApplication1"); if (procs.Length > 0) { SetForegroundWindow(procs[0].MainWindowHandle); procs[0].WaitForInputIdle(); SendKeys.Send(textToSend); SendKeys.Send("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.Send(textToSend2); SendKeys.Send("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.Send(textToSend3); } }

Vulpes · Answer

OK, you first need to add these 'using' directives to the others at the top of the file: using System.Runtime.InteropServices; using System.Diagnostics; Next you need to add this method declaration to your form (I assume it's a windows forms application you have); [DllImport("user32.dll")] private static extern bool SetForegroundWindow(IntPtr hWnd); Finally, if you're going to do this on the press of a button (btnSend say), then you need to add this code to your handler: private void btnSend_Click(object sender, EventArgs e) { string textToSend = "Put something in here"; Process[] procs = Process.GetProcessesByName("Magtek"); if (procs.Length > 0) { SetForegroundWindow(procs[0].MainWindowHandle); procs[0].WaitForInputIdle(); SendKeys.Send(textToSend); } } I'm assuming that the other application is called magtek.exe but, if its called something else, just use the actual name without the .exe part. I'm also assuming that the Magtek application is already running when your application is launched. It would be possible to modify the code to start up the application if it's not already running, but see if it will work like this first of all.

Sam Hobbs · Answer

I certainly consider Sendkeys to be a hit or miss type of solution that can be unreliable and difficult to get correct. I would use the Windows API solution that Vulpes does not like. The Windows API solution can be easier and more reliable. I have not yet read all of this thread; I will try to get back to it later.

Vijay Yadav · Answer

Vulpes, I ahve assign Clipboard .GetText() directly to label text and it shows em the correct value. Now the question is I don't the that another application to get activate over my application, when the serial port connnection gets established that second application( from where I'm copying the data to the label text of my application) gets activate and i don't to show that application to the user.

Vijay Yadav · Answer

Hey Vulpes, string text = Clipboard .GetText(); This is where the catch is. It gives me empty string but if i do right click and paste it in notepad, it gives me the value "USA 20". Do you have any idea why it is happening?

Vijay Yadav · Answer

AAh! No it also shows the blank label text, i think it is not going in that function.

Vulpes · Answer

See if it's any better if you replace 'Invoke' with 'BeginInvoke' which is the asynchronous version of the former.

Vijay Yadav · Answer

Hi Vulpes, Thanks for the reply, now it is not throwing any error but i didn't get any value in the label. It shows blank label text while the expected value is "USA 20".

Vijay Yadav · Answer

Hey Vuples, I am having one qurey. When call the below function it on button click it works fine public void CallMe() { Process[] procs = Process.GetProcessesByName("ID003 Basic Driver v1.6"); if (procs.Length > 0) { SetForegroundWindow(procs[0].MainWindowHandle); procs[0].WaitForInputIdle(); System.Threading.Thread.Sleep(200); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); SendKeys.SendWait("{HOME}"); SendKeys.SendWait("+{END}"); SendKeys.SendWait("^C"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); procs[0].WaitForInputIdle(); SendKeys.SendWait("{TAB}"); SendKeys.SendWait("{ENTER}"); string text = Clipboard.GetText(); label1.Text = text; Regex rex = new Regex(@"\d+"); Match mm = rex.Match(label10.Text); if (mm.Success) { label1.Text = "$ " + mm.Value; } } } but when i call this on timer elapsed event it gives me error, When i am using sendkeys.send , sendkey cannot run inside the application because the application is not handling the window message and on sendkeys.sendwait it gives, Cross-thread operation not valid: Control 'label1' accessed from a thread other than the thread it was Any idea?

Sam Hobbs · Answer

You must expect synchronization issues with problems such as this. Your program is doing what is notmally done by a person. Synchronization is potentially very complicated. if it is too complicated, then you won't know until you have invested a lot of time. If it were me, I would assume from the beginning that it will be complicated to solve and use solutions based on that assumption. Hopefully use of SendKeys will not be too complicated but I would not go that way.

Vulpes · Answer

It's probably a synchronization issue. You could try inserting a short delay before you send the keys to press the button: System.Threading.Thread.Sleep(100); // 0.1 second delay say

Vijay Yadav · Answer

Hi Vulpes, All of a sudden its working fine but now the problem is after 3 textbox there is one button, i want to click the button to perform its action, this also work fine but sometimes the focus go to the button but it doesn't get clicked on both XP and vista both and i don't know why? Do you have suggestion regarding the same??

Vulpes · Answer

It may be a UAC issue as there's a note in the MSDN docs for SendKeys.Send which says: "The SendKeys class has been updated for the .NET Framework 3.0 to enable its use in applications that run on Windows Vista. The enhanced security of Windows Vista (known as User Account Control or UAC) prevents the previous implementation from working as expected." So which version of the .NET Framework are you using and are you running the applications 'as administrator'?

Vijay Yadav · Answer

Hi Vulpes, Now i am running the same application on vista operating system, it opens the other application but it is showing blank textbox instead of value that i am sending from my application. Is anything else that we need to do.

Suthish Nair · Answer

Ha ha.. Vulpes do you like Chilled Beer or Hot.. Superb Man... each of his thread replies deserve points. And Vijay, completed his project on this single thread.. Good work, Thumps Up !!!

Vijay Yadav · Answer

Yes Vulpes is really hard working and he really help others... :)

Mahesh Chand · Answer

Vulpes is a hard working guy! Doing a great job.

Vijay Yadav · Answer

Hi Sam, Can you please suggest somthing more reliable and easy?

Sam Hobbs · Answer

If it were me the first thing I would do is to look for something that the vendor provides for doing that. Are you sure there is not an API for sending the data to the Magtek device? If that is not possible, I would sure avoid using SendKeys and instead do something more reliable and easier than that but since you already have it working I won't go into that.

Vulpes · Answer

Sorry, I should have read the whole thread again! The code to create a hidden window does in fact work (I tried it myself before posting) but, as soon as you call SetForegroundWindow, it becomes visible. There's no way around this with SendKeys because the target window must have the input focus to send keys to it. You should still be able to post messages to a hidden window but it will be very difficult to send keystrokes to the correct controls without some co-operation from the receiving application itself. As a compromise, you could hide the window after you've sent the keystrokes but it will inevitably be visible for a short time.

Vijay Yadav · Answer

Hi Vulpes, It is not working. Again it gets visible. Any other solutions...

Vulpes · Answer

Contrary to what it says in the documentation, if you want the other application to be hidden, then you'll need to set the UseShellExecute property to true. So, you'll need: ProcessStartInfo startInfo = new ProcessStartInfo("MyApp"); startInfo.UseShellExecute = true; startInfo.WindowStyle = ProcessWindowStyle.Hidden; Process.Start(startInfo);

Vijay Yadav · Answer

Hey Vulpes, once again i need your help. As per your method i can send the data to other the application but at the same i want that application to be invisible and it should perform its action. I mean user should not be able to view that another application. I have use this ProcessStartInfo startInfo = new ProcessStartInfo ( "MyApp"); ProcessStartInfo startInfo.WindowStyle = ProcessWindowStyle .Hidden; Process .Start(startInfo);

Vijay Yadav · Answer

Hey Vulpes, thats ok!!!! You really help me out a lot.. thanks man... :)

Vulpes · Answer

Sorry, Vijay, I'm no help on that one :(

Vijay Yadav · Answer

Hi Vulpes, Thanks again!!!! One more, do you have any idea regarding bill acceptor that accepts the bill( i.e. currency) and through serial port it give the values(i.e. currency say $10, $20, etc.) that it detects and show it in the textbox of our application or nay text file. :)

Vijay Yadav · Answer

Hi Vulpes, One more, if i want to read data from their application's tetxbox to my application. Any idea? :)

Vijay Yadav · Answer

Hi, Thanks for your reply!!!! You solution is really good and solved my query... :)

Vulpes · Answer

If it's the default button on the form i.e. the one that gets pressed if you press ENTER from anywhere on the keyboard, then just send the ENTER key after you've populated the textboxes. SendKeys.Send("{ENTER}"); If it isn't the default button, then keep sending the TAB key until focus reaches the button you want. Then send ENTER.

Vijay Yadav · Answer

Hi Vulpes, Thanks Man.. One more query how can i fire button click event through the same..please reply..

Vijay Yadav · Answer

Hi, Thanks a lot Vulpes!!!, you solved my query and just i want to know whether we can send the data on other textbox as well or not which is having focus after the first textbox. Actually there are 3 textboxes to which i have to send the data. Is it possible? Please reply!!!! :)

Vijay Yadav · Answer

Hi, Yes, you are right. The textbox in which i want to send data is the first textbox that receive focus.As you said (force focus onto the application (this can be done programatically) and then send the text using SendKeys.Send()) i want to know how to do this. Please reply!!! :)

Vulpes · Answer

I'm afraid I'm not familiar with the Magtek application so I don't know what it can and can't do. One other way that might work is to force focus onto the application (this can be done programatically) and then send the text using SendKeys.Send(). However, this will only work if the textbox which is receiving the text will be the first control to receive input focus when the application itself receives focus. Do you know whether this is the case?

Vijay Yadav · Answer

Hi Vulpes, Thanks again for replying, but i don't whether there is a way to pick up data from a file or not, because that application is developed by Magtek, which comes with the Magtek encoder now i want to send data from my application to their. Any Idea?

Vulpes · Answer

There is a way to send text directly to another application's textbox using the Win32 API but you need to know the textbox's name so that you can get its window handle. Frankly, it's a bit of a 'hit and miss' affair even if you have all the info available! Can the other application pick up data from a file? If so, then you could write it to a file (encrypted if necessary) from your application.

Vijay Yadav · Answer

Hi Vulpes, Thanks a lot for the reply. And its good to know about the clipboard. But it is not secure way, is there any other way for this to get data. Please Help!!!!!

Vulpes · Answer

If the other .exe is running on the same machine as your application, then a simple way would be to copy text on to the Clipboard programatically from the latter. You can then manually paste this into the other application's textbox. private void button1_Click(object sender, EventArgs e) { Clipboard.SetText("Hello"); MessageBox.Show("Text has been copied to the clipboard!"); }

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