Log Class

Definition

public ref class Log

public class Log

type Log = class

Public Class Log

Inheritance

Object

Log

Derived

Microsoft.VisualBasic.Logging.AspLog

Examples

This example shows how to use the My.Application.Log.WriteEntry method to log tracing information. For more information, see How to: Write Log Messages.

Private Sub GetOpenFormTitles()
    Dim formTitles As New Collection

    Try
        For Each f As Form In My.Application.OpenForms
            ' Use a thread-safe method to get all form titles.
            formTitles.Add(GetFormTitle(f))
        Next
    Catch ex As Exception
        formTitles.Add("Error: " & ex.Message)
    End Try

    Form1.ListBox1.DataSource = formTitles
End Sub

Private Delegate Function GetFormTitleDelegate(f As Form) As String
Private Function GetFormTitle(f As Form) As String
    ' Check if the form can be accessed from the current thread.
    If Not f.InvokeRequired Then
        ' Access the form directly.
        Return f.Text
    Else
        ' Marshal to the thread that owns the form. 
        Dim del As GetFormTitleDelegate = AddressOf GetFormTitle
        Dim param As Object() = {f}
        Dim result As System.IAsyncResult = f.BeginInvoke(del, param)
        ' Give the form's thread a chance process function.
        System.Threading.Thread.Sleep(10)
        ' Check the result.
        If result.IsCompleted Then
            ' Get the function's return value.
            Return "Different thread: " & f.EndInvoke(result).ToString
        Else
            Return "Unresponsive thread"
        End If
    End If
End Function

Remarks

The My.Application.Log object provides a straightforward entry point from which to access the .NET Framework's logging services. The WriteEntry and WriteException methods write messages to the application's log listeners. The listeners can be configured by the application's configuration file. For more information, see Walkthrough: Changing Where My.Application.Log Writes Information and Working with Application Logs.

The My.Application.Log object is available only for client applications. For Web applications, use My.Log. For more information, see AspLog.

The following table lists examples of tasks involving the My.Application.Log object.

See also

• Objects (Visual Basic)