DebuggerDisplayAttribute Class
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DebuggerDisplayAttribute Class


Determines how a class or field is displayed in the debugger variable windows.

Namespace:   System.Diagnostics
Assembly:  mscorlib (in mscorlib.dll)


<AttributeUsageAttribute(AttributeTargets.Assembly Or AttributeTargets.Class Or AttributeTargets.Struct Or AttributeTargets.Enum Or AttributeTargets.Property Or AttributeTargets.Field Or AttributeTargets.Delegate,
	AllowMultiple := True)>
Public NotInheritable Class DebuggerDisplayAttribute
	Inherits Attribute


Initializes a new instance of the DebuggerDisplayAttribute class.


Gets or sets the name to display in the debugger variable windows.


Gets or sets the type of the attribute's target.


Gets or sets the type name of the attribute's target.


Gets or sets the string to display in the type column of the debugger variable windows.


When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)


Gets the string to display in the value column of the debugger variable windows.


This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.)


Returns the hash code for this instance.(Inherited from Attribute.)


Gets the Type of the current instance.(Inherited from Object.)


When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)


When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)


Returns a string that represents the current object.(Inherited from Object.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.)


Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

The DebuggerDisplayAttribute constructor has a single argument: a string to be displayed in the value column for instances of the type. This string can contain braces ({ and }). The text within a pair of braces is evaluated as the name of a field, property, or method. For example, the following C# code causes "Count = 4" to be displayed when the plus sign (+) is selected to expand the debugger display for an instance of MyHashtable.

[DebuggerDisplay("Count = {count}")]
class MyHashtable
    public int count = 4;

For information about using this attribute in Visual Studio, see Using DebuggerDisplay Attribute.

View the following example in Visual Studio to see the results of applying the DebuggerDisplayAttribute.

Imports System
Imports System.Collections
Imports System.Diagnostics
Imports System.Reflection

Class DebugViewTest
    ' The following constant will appear in the debug window for DebugViewTest.
    Const TabString As String = "    "
    ' The following DebuggerBrowsableAttribute prevents the property following it
    ' from appearing in the debug window for the class.
    <DebuggerBrowsable(DebuggerBrowsableState.Never)> _
    Public Shared y As String = "Test String"

    Shared Sub Main() 
        Dim myHashTable As New MyHashtable()
        myHashTable.Add("one", 1)
        myHashTable.Add("two", 2)
        Console.WriteLine("In Main.")

    End Sub 'Main 
End Class 'DebugViewTest
<DebuggerDisplay("{value}", Name := "{key}")>  _
Friend Class KeyValuePairs
    Private dictionary As IDictionary
    Private key As Object
    Private value As Object

    Public Sub New(ByVal dictionary As IDictionary, ByVal key As Object, ByVal value As Object) 
        Me.value = value
        Me.key = key
        Me.dictionary = dictionary

    End Sub 'NewNew
End Class 'KeyValuePairs
<DebuggerDisplay("Count = {Count}"), DebuggerTypeProxy(GetType(MyHashtable.HashtableDebugView))> _
Class MyHashtable
    Inherits Hashtable
    Private Const TestString As String = "This should not appear in the debug window."

    Friend Class HashtableDebugView
        Private hashtable As Hashtable
        Public Shared TestString As String = "This should appear in the debug window."

        Public Sub New(ByVal hashtable As Hashtable)
            Me.hashtable = hashtable
        End Sub 'NewNew

        <DebuggerBrowsable(DebuggerBrowsableState.RootHidden)> _
        ReadOnly Property Keys as KeyValuePairs()
                Dim nkeys(hashtable.Count) as KeyValuePairs

                Dim i as Integer = 0
                For Each key As Object In hashtable.Keys
                    nkeys(i) = New KeyValuePairs(hashtable, key, hashtable(key))
                    i = i + 1
                Return nkeys
            End Get
        End Property

    End Class 'HashtableDebugView
End Class 'MyHashtable

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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