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Manipulating Simple Windows Calculator Using win32 API in C #?

Well, I tried my best to look at code examples and messages all over the Internet on how to do this, but I could not succeed after a few months using the Windows API to interact with another which is already running. I am not the best programmer, and some of these things are outside of me.

The most I could do was find the calculator process and its handle and use it with SetWindowText to change the title. What I really would like to know how to do is make my program using Windows user32 (I think it should be the right library) to enter some numbers, actually pressing the number keys on the software calculator to make it simple payment.

I really have no use for this program, it is just a goal that I am trying to understand in order to learn how to use the window API at my very entry level SPECIFICALLY in C #. If someone does not have the code for this, or even if you do, I would best appreciate some of the suggestions on books or resources on the Internet that I have to read to find out how to do this.

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2 answers

Since you say that you use C #, you should use a namespace System.Windows.Automationwhose purpose in life is to allow you to control other programs using automation.

You did not provide details about what you want, but here is a program that pushes "7" into the calculator.

using System.Windows.Automation;

class Program
{
 public static void Main()
 {
  var calcWindow = AutomationElement.RootElement.FindFirst(
   TreeScope.Children,
   new PropertyCondition(AutomationElement.NameProperty, "Calculator"));
  if (calcWindow == null) return;

  var sevenButton = calcWindow.FindFirst(TreeScope.Descendants,
   new PropertyCondition(AutomationElement.NameProperty, "7"));

  var invokePattern = sevenButton.GetCurrentPattern(InvokePattern.Pattern)
                     as InvokePattern;
  invokePattern.Invoke();
 }
}
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You enter the fun world of platform calling (P / Invoke). Your best friend in this world is www.pinvoke.net , which contains C # (and vb.net) signatures for a large number of winapi functions.

For example SendMessage:

[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);

and this list of message codes .

, p/invoke DllImport, System.Runtime.InteropServices.

extern . , .

SendMessage .

, Spy ++, , , , .

- P/Invoke.

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