19. Define the TrackBar control.
The TrackBar control, also known as the slider control, works as a navigator to display a large amount of information or for visual adjustment of numeric setting. There are two parts in a TrackBar control – thumb (also known as slider) and tick marks. The thumb part acts as a slider. You can adjust the thumb part using the Value property. The tick marks are visual indicators that are spaced at regular intervals.
20. How does an MDI form differ from a standard form?
An MDI form closely resembles a standard form with one major difference-the client area of an MDI form acts as a container for other forms. It means that an MDI form, also known as an MDI parent form, can display MDI child forms inside it.
21. Which method provides the functionality to display a dialog box at runtime?
The ShowDialog() method is used to display the dialog box at run time.
22. What does the PerformStep() method do?
The PerformStep() method increases the value of Progress bar according to the amount set by the Stepproperty.
23. Write a method to get only the name of a file from the complete path string in C#.
Use a FileInfo class and instantiate its object with the full path as the constructor argument and then simply call the FileInfo.Name file and you will get just the name of the file.
24. What does the OpenFile() method of the OpenFileDialog control do?
The OpenFile() method opens the file selected by the user with read-only permission. The file is specified by the FileName property.