code snippet to build my eReader application

1. Check if a specific tab page is selected (active)
2. TabControl.SelectedTab Property
3. Display the selected row from listview to textBox?
4. Path.Combine Method (String, String)
5. What is the best way to combine a path and a filename in C#/.NET?
6. C# tip: Use Path Combine for file or directory path information
7. Why does Path.Combine not properly concatenate filenames that start with Path.DirectorySeparatorChar?
8. System.IO.Path.Combine to merget file path in c#
9. How to get Adobe Reader full path(including executable file name)?
10. Registry Class
11. Registry.GetValue Method (String, String, Object)
12. Initialize value of 'var' in C# to null [duplicate]
13. How to initialize var?
14. PDF Viewer Control Without Acrobat Reader Installed
15. What is Sumatra PDF?
16. a lightweight PDF and XPS viewer
17. .NET open PDF in winform without external dependencies