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Thread.ThreadState Property

Gets a value containing the states of the current thread.

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

'Declaration
Public ReadOnly Property ThreadState As ThreadState
'Usage
Dim instance As Thread 
Dim value As ThreadState 

value = instance.ThreadState

Property Value

Type: System.Threading.ThreadState
One of the ThreadState values indicating the state of the current thread. The initial value is Unstarted.

The ThreadState property provides more specific information than the IsAlive property.

Important noteImportant Note:

Thread state is only of interest in debugging scenarios. Your code should never use thread state to synchronize the activities of threads.

The following code example demonstrates accessing the ThreadState of a thread.

Imports Microsoft.VisualBasic
Imports System
Imports System.Threading

Public Class ApartmentTest

    <MTAThread> _
    Shared Sub Main()

        Dim newThread As Thread = New Thread(AddressOf ThreadMethod)
        newThread.SetApartmentState(ApartmentState.MTA)

        ' The following line is ignored since  
        ' ApartmentState can only be set once.
        newThread.SetApartmentState(ApartmentState.STA)

        Console.WriteLine("ThreadState: {0}, ApartmentState: {1}", _
            newThread.ThreadState, newThread.GetApartmentState())

        newThread.Start()

        ' Wait for newThread to start and go to sleep.
        Thread.Sleep(300)
        Try 
            ' This causes an exception since newThread is sleeping.
            newThread.SetApartmentState(ApartmentState.STA)
        Catch stateException As ThreadStateException
            Console.WriteLine(vbCrLf & "{0} caught:" & vbCrLf & _
                "Thread is not In the Unstarted or Running state.", _
                stateException.GetType().Name)
            Console.WriteLine("ThreadState: {0}, ApartmentState: " & _
                "{1}", newThread.ThreadState, newThread.GetApartmentState())
        End Try 

    End Sub 

    Shared Sub ThreadMethod()
        Thread.Sleep(1000)
    End Sub 

End Class

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
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