Testing and Debugging Managed Applications

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Testing and Debugging Managed Applications
Nick Randolph .NET CF MVP
VS2005 User Group Launch
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Agenda

• Test Driven Development
• Developing code
• Object data binding
• Debugging running code

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Test Driven Development

• Does NOT imply NO design
• Design class functionality
• Write test cases to define class behaviour
• Implement class to pass test cases

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Class Designer

• Why?
• Understanding Existing Code
• Class Design
• Review/Refactor
• Documentation

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Class Designer - Toolbox

• Design space objects
• Class
• Interface
• Structure
• .
• Connectors
• Inheritance (implements)
• Association (collections)

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Class Designer Code Alive

• Dynamic representation of code
• .cd file xml meta-data
• Complete code round-tripping

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Class Details

• Properties, Methods, Fields, Events
• Name, Type, Modifier, Summary, Hide
• Parameters
• Tree structure tab, intellisense

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Class Details

• Properties Window
• Access
• Accessor
• Custom Attributes
• Filename
• Full Name
• Generic
• Implements
• Inheritance Modifier
• Inherits
• .

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Demo

• Design Customer class
• Name
• Design Order class
• Description
• Quantity
• Date ordered

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Unit Testing

• Precursor NUnit Framework
• Test stub creation
• Test framework for execution and reporting

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Unit Testing Attributes

• Nunit Team Suite
• TestFixture TestClass
• Test TestMethod
• TestFixtureSetup ClassInitialize
• TestFixtureTearDown ClassCleanup
• Setup TestInitialize
• TearDown TestCleanup

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Demo

• Building and executing test stubs
• Completing Customer/Order classes

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Object Workbench

• Design-time tool for debugging
• Create class instance with running application up
  or test framework
• Class View
• Class Diagram
• Probe instance
• Modify properties or fields
• Invoke methods
• Store return values

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Demo

• Creating and probing objects with the workbench

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Drag n Drop UI Development

• Data source window
• Data source types
• Data sets
• Webservices
• Objects
• Two views
• Data type (eg integers, strings)
• Display view (when working with UI designer)

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Drag n Drop UI Development

• Drag n Drop Object Binding
• Display options (datagridview or details)
• Binding controls
• BindingSource
• BindingNavigator

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Demo

• Wiring up the Customer class for editting

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Tangent Using Settings to Persist Data

• Application/User Settings
• VB.NET
• My Namespace
• Strong typing of settings under My.Settings
• Application Framework
• Auto save settings on close

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Demo

• Create User Setting
• Modifying user setting to save Customer list

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Debugging Support

• Immediate Window
• Break and Tracepoint Window
• New breakpoint dialogs
• Ability to run macros and write output without
  breaking
• Edit Continue

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Demo

• Immediate execution without application in Debug
• Setting break/trace points to track application
  progress
• Modifying code while application paused

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Debugger

• Debugger.IsAttached
• Determine if a debugger is attached
• Debugger.Launch
• Launches a debugger (if not attached)
• Debugger.Break
• Equivalent to a breakpoint
• Will launch the debugger if not attached

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Debugging

• DebuggerDisplay
• Single line representation
• Hover over object
• Can add property values
• DebuggerBrowsable
• C
• Determines whether the variable/property is
  collapsed, never displayed, root hidden or
  expanded

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Demo

• DebuggerDisplay showing use of parameters

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Debugging

• DebuggerHidden
• Debugger wont stop in method, property or
  constructor
• Cant set breakpoints in there either
• DebuggerNonUserCode
• Class/Structure, Method, Constructor, Property
• Prevents stepping into and appearance in UserCode
  section of call stack

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Debugging

• DebuggerStepThrough
• Debugger wont step into method
• Will stop for breakpoints
• DebuggerTypeProxy
• Shows alternative type instead of type being
  debugged
• Must have a constructor with single argument of
  the type being debugged
• DebuggerVisualizer
• Allows user code to run when magnifier is
  selected
• Must inherit from DialogDebuggerVisualizer

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Demo

• Create a property that modifies a value when Get
  is executed
• Use DebuggerTypeProxy to prevent execution
• Create a visualiser to represent data

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Questions?