Log.WriteEntry Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Writes a message to the application's log listeners.
Overloads
| WriteEntry(String) |
Writes a message to the application's log listeners. |
| WriteEntry(String, TraceEventType) |
Writes a message to the application's log listeners. |
| WriteEntry(String, TraceEventType, Int32) |
Writes a message to the application's log listeners. |
WriteEntry(String)
- Source:
- Log.vb
- Source:
- Log.vb
- Source:
- Log.vb
Writes a message to the application's log listeners.
public:
void WriteEntry(System::String ^ message);public void WriteEntry(string message);member this.WriteEntry : string -> unitPublic Sub WriteEntry (message As String)Parameters
- message
- String
Required. The message to log. If message is Nothing, an empty string is used.
Exceptions
Code with partial trust calls the method, but writes to an event log listener that requires full trust.
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
This code example can run only within a client application. Change My.Application.Log.WriteEntry to My.Log.WriteEntry for Web applications.
Remarks
The WriteEntry method writes a message to the application's event log listeners.
In client applications, the Log object is available through the My.Application.Log object. In Web applications, the Log object is available through the My.Log object.
To learn which log listeners receive the WriteEntry method's messages, see Walkthrough: Determining Where My.Application.Log Writes Information. You can change default log listeners. For more information, see Working with Application Logs.
For overloads that do not take the id argument, the id written to the log is defined by the following table.
severity |
Default id |
|---|---|
| Information | 0 |
| Warning | 1 |
| Error | 2 |
| Critical | 3 |
| Start | 4 |
| Stop | 5 |
| Suspend | 6 |
| Resume | 7 |
| Verbose | 8 |
| Transfer | 9 |
The following table lists examples of tasks involving the WriteEntry method.
| To | See |
|---|---|
| Write event information to the application's log listeners | How to: Write Log Messages |
Determine where Log writes information |
Walkthrough: Determining Where My.Application.Log Writes Information |
Availability by Project Type
| Project type | Available |
|---|---|
| Windows Application | Yes |
| Class Library | Yes |
| Console Application | Yes |
| Windows Control Library | Yes |
| Web Control Library | No |
| Windows Service | Yes |
| Web Site | Yes |
See also
- TraceEventType
- Objects (Visual Basic)
- Working with Application Logs in Visual Basic
- How to: Write Log Messages
- Walkthrough: Determining Where My.Application.Log Writes Information
Applies to
WriteEntry(String, TraceEventType)
- Source:
- Log.vb
- Source:
- Log.vb
- Source:
- Log.vb
Writes a message to the application's log listeners.
public:
void WriteEntry(System::String ^ message, System::Diagnostics::TraceEventType severity);public void WriteEntry(string message, System.Diagnostics.TraceEventType severity);member this.WriteEntry : string * System.Diagnostics.TraceEventType -> unitPublic Sub WriteEntry (message As String, severity As TraceEventType)Parameters
- message
- String
Required. The message to log. If message is Nothing, an empty string is used.
- severity
- TraceEventType
The type of message. By default, TraceEventType.Information.
Exceptions
The message type is not one of the TraceEventType enumeration values.
Code with partial trust calls the method, but writes to an event log listener that requires full trust.
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
This code example can run only within a client application. Change My.Application.Log.WriteEntry to My.Log.WriteEntry for Web applications.
Remarks
The WriteEntry method writes a message to the application's event log listeners.
In client applications, the Log object is available through the My.Application.Log object. In Web applications, the Log object is available through the My.Log object.
To learn which log listeners receive the WriteEntry method's messages, see Walkthrough: Determining Where My.Application.Log Writes Information. You can change default log listeners. For more information, see Working with Application Logs.
For overloads that do not take the id argument, the id written to the log is defined by the following table.
severity |
Default id |
|---|---|
| Information | 0 |
| Warning | 1 |
| Error | 2 |
| Critical | 3 |
| Start | 4 |
| Stop | 5 |
| Suspend | 6 |
| Resume | 7 |
| Verbose | 8 |
| Transfer | 9 |
The following table lists examples of tasks involving the WriteEntry method.
| To | See |
|---|---|
| Write event information to the application's log listeners | How to: Write Log Messages |
Determine where Log writes information |
Walkthrough: Determining Where My.Application.Log Writes Information |
Availability by Project Type
| Project type | Available |
|---|---|
| Windows Application | Yes |
| Class Library | Yes |
| Console Application | Yes |
| Windows Control Library | Yes |
| Web Control Library | No |
| Windows Service | Yes |
| Web Site | Yes |
See also
- TraceEventType
- Objects (Visual Basic)
- Working with Application Logs in Visual Basic
- How to: Write Log Messages
- Walkthrough: Determining Where My.Application.Log Writes Information
Applies to
WriteEntry(String, TraceEventType, Int32)
- Source:
- Log.vb
- Source:
- Log.vb
- Source:
- Log.vb
Writes a message to the application's log listeners.
public:
void WriteEntry(System::String ^ message, System::Diagnostics::TraceEventType severity, int id);public void WriteEntry(string message, System.Diagnostics.TraceEventType severity, int id);member this.WriteEntry : string * System.Diagnostics.TraceEventType * int -> unitPublic Sub WriteEntry (message As String, severity As TraceEventType, id As Integer)Parameters
- message
- String
Required. The message to log. If message is Nothing, an empty string is used.
- severity
- TraceEventType
The type of message. By default, TraceEventType.Information.
- id
- Int32
Message identifier, typically used for correlation. By default, related to entryType as described in the table.
Exceptions
The message type is not one of the TraceEventType enumeration values.
Code with partial trust calls the method, but writes to an event log listener that requires full trust.
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
This code example can run only within a client application. Change My.Application.Log.WriteEntry to My.Log.WriteEntry for Web applications.
Remarks
The WriteEntry method writes a message to the application's event log listeners.
In client applications, the Log object is available through the My.Application.Log object. In Web applications, the Log object is available through the My.Log object.
To learn which log listeners receive the WriteEntry method's messages, see Walkthrough: Determining Where My.Application.Log Writes Information. You can change default log listeners. For more information, see Working with Application Logs.
For overloads that do not take the id argument, the id written to the log is defined by the following table.
severity |
Default id |
|---|---|
| Information | 0 |
| Warning | 1 |
| Error | 2 |
| Critical | 3 |
| Start | 4 |
| Stop | 5 |
| Suspend | 6 |
| Resume | 7 |
| Verbose | 8 |
| Transfer | 9 |
The following table lists examples of tasks involving the WriteEntry method.
| To | See |
|---|---|
| Write event information to the application's log listeners | How to: Write Log Messages |
Determine where Log writes information |
Walkthrough: Determining Where My.Application.Log Writes Information |
Availability by Project Type
| Project type | Available |
|---|---|
| Windows Application | Yes |
| Class Library | Yes |
| Console Application | Yes |
| Windows Control Library | Yes |
| Web Control Library | No |
| Windows Service | Yes |
| Web Site | Yes |
See also
- TraceEventType
- Objects (Visual Basic)
- Working with Application Logs in Visual Basic
- How to: Write Log Messages
- Walkthrough: Determining Where My.Application.Log Writes Information
