Teach Yourself Borland C++ in 14 Days - portal

424 Day 11
Q I have a variable that I want to view in both decimal and hexadecimal format.
Can I do that with the Watch List?
A Yes. First add the variable to the Watch List. When the Watch Properties dialog
box comes up, choose the Decimal viewing option. Now add the variable again,
but this time choose the Hexadecimal viewing option. Both items will be listed in
the Watch List, one in decimal format and the other in hex format.
Q I’m trying to add the Width property of a component on my form to the Watch
List. I get some strange error like, “Pointer to structure required on left side of
something or another.” What am I doing wrong?
A You can’t inspect a property of a component using the Watch List. You can,
however, inspect the component using the Debug Inspector and locate the FWidth
data member rather than the Width property. (The FWidth data member holds the
value of the Width property.)
Q I want to stop at a breakpoint only when a variable reaches a certain value and
after the breakpoint has been hit a certain number of times. Can I do that?
A Sure. Enter a conditional expression in the Condition field of the Edit Breakpoint
dialog box and a value in the Pass Count field. When the condition is met for the
number of times indicated by the pass count, the program will pause at the
breakpoint.
Q I’m stepping through my code, and I get to a function in my program that I
want to debug. When I press F8, the execution point jumps right over the
function instead of going into it. What do I do to get into that function?
A When the execution point is on the line where the function is called, press F7
(Trace Into) instead of F8. Now you can step through the function a line at a time.
Q When I step through my code, the execution point jumps all over the place
rather than proceeding through my code a line at a time. What causes that?
A In a word: optimization. If you want to be able to debug your program one source
code line at a time, sequentially, turn off all optimizations and then do a Build All
to rebuild the project.
Q I step through a function line by line. Sometimes when I get to the closing
brace of the function I press F8 one more time and nothing happens. Why?
A Because when that particular function returns, your program has nothing more to
do, so it goes back into its idle state. Essentially, there is no more code to step
through at that point, so the debugger returns control to the program being
debugged.
Q How do I use the CPU View when debugging?
A Just choose View | CPU from the main menu to display the CPU View. Knowing
what to do with the CPU View, however, is another matter entirely!