Debugging in Visual Studio

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Debugging in Visual Studio
Materials used in this presentation may be
downloaded from acm . southalabama . edu /
Mothra / debug /

• Timothy Lee J00220066
• ITE 370 Ms. Chapman
• Technical Presentation 04-10-07

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What is a bug?
Materials used in this presentation may be
downloaded from acm . southalabama . edu /
Mothra / debug /

• A fault occurs when a human makes an error.
• A failure is any departure from a systems
  required behavior.

From Software Engineering, 3rd Edition, by Shari
Lawrence Pfleeger and Joanne Atlee, 2006 Pearson
Education Inc., Upper Saddle River, NJ
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Types of Errors
Materials used in this presentation may be
downloaded from acm . southalabama . edu /
Mothra / debug /

• Syntax Errors-any error that prevents the
  program from compiling and executing.
• Execution Errors-any statement that attempts to
  perform an illegal operation.
• Logic Errors-any statement that executes
  successfully, but doesnt perform as expected,
  usually due to a human computational error.

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Breakpoints

• Continue
• Break (pause execution)
• Stop Debugging (quit execution)
• Restart
• Show Next Statement
• Step Into
• Step Over
• Step Out

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Breakpoints (continued)

• SHORTCUT KEYS
• Start/Continue F5
• Stop ShiftF5
• Restart CtrlShiftF5
• Step Into F11
• Step Over F10
• Step Out ShiftF11

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Customizing Breakpoints

• Conditions only break if condition is true
• Hit Count times a breakpoint has been
  reached can set to stop breaking after a
  certain count
• Tracepoints print string when breakpoint is
  reached
• option to not break when breakpoint reached
• Run To Cursor execute program and break at
  cursor position

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Managing Breakpoints

• Disable/Enable All Breakpoints(Debug main menu)
• Breakpoints Window
• (Debug main menu -gt Windows -gt Breakpoints)
• - allows user to view all Breakpoints an a
  program, jump to their code, edit their
  properties, enable/disable and delete.

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Call Stack

• Displays all currently executing procedures in
  the order that they have been called.
• Will link you to specific procedures.

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Immediate Window

• View current variablesType ?
  variableNames
• Change variables valuestype varialbeName
  value

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Calls to the Debug Class

• There exists a System.Diagnostics.Debug Class.
  With multiple tools available to aid debugging.
• Debug.Assert(condition, message, detailed
  message)create custom error messages that
  display only when a condition is true.
• Debug.WriteLine(message)alternative to
  Console.WriteLine( )
• When you compile your program as a release build,
  these objects are disabled, saving you the time
  of going through and removing Console.PrintLine
  statements.

Explore additional members of Debug
at http//msdn2.microsoft.com/en-us/library/syst
em.diagnostics.debug_members.aspx
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Visualizations

• Autos Window
• shows variables used by the current and previous
  statements.
• Locals Windowshows all of the variables in the
  current scope
• Quick Watch Watch Windowshows only variables
  you attach to a Watch Window
• Windows display the name, value, and type of
  variables. Gives you the ability to manually
  change values using a visual interface rather
  than typing text commands.

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Data Visualizers

• When a program is paused, hovering the cursor
  over a variables will display its value.
• For complex datatypes, you can view either a
  text, html, or xml Visualizer presenting an
  organized view of the data.