Teach Yourself Borland C++ in 14 Days - portal

412 Day 11
Other Debugging Tools
C++Builder has some additional debugging tools to aid you in tracking down bugs. Some of
these tools are, by nature, advanced debugging tools. Although the advanced debugging tools
are not as commonly used as the other tools, they can be very powerful in the hands of an
experienced programmer.
Evaluate/Modify
The Evaluate/Modify dialog box allows you to inspect the current value of a variable and to
modify the value of a variable if you want. Using this dialog box, you can test for different
outcomes by modifying a particular variable. This allows you to play a what-if game with your
program as it runs. Figure 11.8 shows the Evaluate/Modify dialog box inspecting an integer
variable called x.
Figure 11.8.
The Evaluate/Modify
dialog box.
The Evaluate/Modify dialog box works similarly to the Watch List or the Debug Inspector.
If you click on a variable in the source code and choose Evaluate/Modify from the Code
Editor speed menu, the variable will be evaluated. If you want to enter a value that is not
currently showing in the source code, you can choose Run | Evaluate/Modify from the main
menu and then type a variable name to evaluate.
The Evaluate field is used to enter the variable name or expression you want to evaluate.
When you click the Evaluate button (or press Enter), the expression will be evaluated and the
result displayed in the Result field.
TIP
The Evaluate/Modify dialog box can be used as a quickie calculator.
You can enter hex or decimal numbers (or a combination) in a mathematical
formula and have the result evaluated. For instance, if you
type
0x400 - 256