After you have called the DLL, InstallOptions adds one value to +
After you have called the DLL, InstallOptions adds one string to the stack, with one of the following values:
Usually, you don't need to check this value, but you still have to remove it from the stack (have a look at the example above).
-If you want to check the user input immediately, for example, to -display a warning when the input is invalid, you should check -whether the user has pressed the Back or Next button.
+You only have to check this value if you need something really +special, such as doing something when the user pressed the Back +button.