Recipe 5.10 Configuring Breakpoint Conditions

5.10.1 Problem

You want to halt a program when a certain condition occurs in your code, such as when a variable contains a certain value.

5.10.2 Solution

Configure your breakpoint to respond to the condition you specify. You do that by right-clicking the breakpoint in the Breakpoints view, clicking Properties, checking the "Enable Condition" checkbox, and entering the condition you want to use (such as loopIndex == 2).

5.10.3 Discussion

To demonstrate how this works, we're setting the condition for a breakpoint to loopIndex == 2 in Figure 5-17.

Figure 5-17. Setting a breakpoint's condition

Now the breakpoint will be active when it's encountered, and when the value in loopIndex equals 2.

You also can break when the value of a condition changes. For example, if some part of your code is changing the value in a variable named loopIndex and it shouldn't, you can type that variable name into the Condition box and check the "value of condition changes" checkbox. (You can use any valid expression in the Condition box, not just variable names.)

5.10.4 See Also

Recipe 5.9 on setting hit counts for breakpoints; Recipe 5.8 on watching expression and variable values.