I want to write an application that will automatically detect and fill the text field in the window shown below:

(assuming the data to be entered is in a file).
The question is how does my application find this text field?
I can do this job if I am able to find the location of the text field on the desktop through program.
Can someone help me understand possible ways for finding this text field?
I am using Windows Form application in C++.
Update:
I played with spy++.
I used spy++, to find the window handle. I did it by putting finder on the window I am interested in. Its giving handle in hex values: 00080086 (actually just for testing purpose I put the finder tool on Visual Studio new project page ). How do I interpret this Hex value into meaningful window name ?
See the below figure.
What is the next step to get to the text field ” Enter name” under “name” field.
****Any sample code will be highly appreciated.**
I am open to any solution not necessarily how I am doing this.

One solution is to use the Microsoft UI Automation technology. It’s shipped out-of-the-box with Windows since Vista. It’s usable from .NET but also from C++ using COM.
Here is a short C++ console application example that displays the class name of the UI Automation Element currently at the middle of the desktop window, each second (you can have it run and see what it displays):
From this sample, what you can do is launch the application you want to automate and see if the sample detects it (it should).
You could also use the UISpy tool to display the full tree of what can be automated in your target app. You should see the windows and other elements (text field) of this target app and you should see the element displayed by the console application example.
From the
pElementdiscovered in the sample, you can call FindFirst with the proper condition (class name, name, control type, etc…) to get to the text field. From this text field, you would use one of the UI Automation Patterns that should be available (probably TextPattern or ValuePattern) to get or set the text itself.The cool thing is you can use the UISpy tool to check all this is possible before actually coding it.