StateChanged Event

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Visual Basic (Declaration)
Visual Basic (Usage)
C#
Managed Extensions for C++
C++/CLI

Raised when the value of the State property changes.

Syntax

Visual Basic (Declaration)
Visual Basic (Usage)
C#
Managed Extensions for C++
C++/CLI

Public Event StateChanged As EventHandler

Dim instance As TcpBase
Dim handler As EventHandler
 
AddHandler instance.StateChanged, handler

public event EventHandler StateChanged

public: __event EventHandler* StateChanged

public:
event EventHandler^ StateChanged

See the SynchronizingObject property for information on updating UI controls in your event handler.

This event can be raised during a Read call if the remote host closes the connection. In this scenario, a form should not be disposed of within this event handler if the Dart component was created on the form (this includes calling Form.Close if Form.Show was used to show it). Instead, the component can be created elsewhere and passed to the form, or the form can be disposed of after the posted Read returns.

This example demonstrates using the StateChanged event and State property to update the UI.

private void myComponent_StateChanged(object sender, EventArgs e)
{
    if (myComponent.State == ConnectionState.Closed)
        this.Text = "Not Connected";
    else if (myComponent.State == ConnectionState.Connected)
        this.Text = "Connected to " + myComponent.RemoteEndPoint.ToString();
    else
        this.Text = "Securely connected to " + myComponent.RemoteEndPoint.ToString();
}

Visual Basic

Private Sub myComponent_StateChanged(ByVal sender As Object, ByVal e As EventArgs)
    If myComponent.State = ConnectionState.Closed Then
        Me.Text = "Not Connected"
    ElseIf myComponent.State = ConnectionState.Connected Then
        Me.Text = "Connected to " & myComponent.RemoteEndPoint.ToString()
    Else
        Me.Text = "Securely connected to " & myComponent.RemoteEndPoint.ToString()
    End If
End Sub

Reference