Debugging Tools – Breakpoints, Watch, Output Window

Using Breakpoints

A breakpoint pauses program execution at a specific line so you can inspect the current state of the application.

• Click in the margin next to the code line, or press F9
• Use F5 to start debugging
• Use F10 (Step Over) or F11 (Step Into) to navigate

int a = 5;
int b = 0;
int result = a / b; // Set a breakpoint here to inspect the crash
Console.WriteLine(result);

Conditional Breakpoints

You can set conditions so that the breakpoint only triggers when certain criteria are met.

• Right-click on the red breakpoint dot → Conditions
• Example: Only break when counter == 10

Watch Window

The Watch window allows you to monitor the values of specific variables or expressions while debugging.

• Open from Debug → Windows → Watch → Watch 1
• Type variable names or custom expressions
• Supports nested objects and collections

Locals and Autos Windows

These windows show local variables and recently used values:

• Locals: Displays all variables in the current scope
• Autos: Shows variables used around the current line

Output Window

The Output window displays real-time logs during build, run, and debug:

• Build Output: Compiler messages and diagnostics
• Debug Output: Custom trace/debug logs using Debug.WriteLine()

using System.Diagnostics;

Debug.WriteLine("This goes to the Output window.");

Immediate Window

Execute expressions, call methods, or evaluate variables live during a paused debug session.

• Open via Debug → Windows → Immediate
• Example: Type myList.Count to check list size

Mastering these debugging tools will make your development process faster and more efficient. In the next lesson, we’ll explore how to manage large solutions with multiple projects and dependencies.