Write Method (String, String)
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TraceContext.Write Method (String, String)

 

Writes trace information to the trace log, including a message and any user-defined categories.

Namespace:   System.Web
Assembly:  System.Web (in System.Web.dll)

Public Sub Write (
	category As String,
	message As String
)

Parameters

category
Type: System.String

The trace category that receives the message.

message
Type: System.String

The trace message to write to the log.

Every time the Write method is called, a TraceContext trace message is added to the TraceRecords messages collection, which is accessible when you handle the TraceFinished event. The message is added with its IsWarning property set to false and its ErrorInfo property set to null.

The following code example demonstrates how to call the Write method to write an error trace message to the trace log. In this example, the delegate iterates through the trace messages and writes them as an HTML table; however, you can write the same information to a database or a profiling tool consumer.

<%@ Page language="VB" Trace="true" %>
<script runat="server">
' The Page_Load method.
Private Sub Page_Load(sender As Object, e As EventArgs)

    ' Register a handler for the TraceFinished event.
    AddHandler Trace.TraceFinished, AddressOf OnTraceFinished

    ' Write a trace message.
    Trace.Write("Web Forms Infrastructure Methods", "USERMESSAGE: Page_Load complete.")
End Sub ' Page_Load

' A TraceContextEventHandler for the TraceFinished event.
Private Sub OnTraceFinished(sender As Object, e As TraceContextEventArgs)

    Dim r As TraceContextRecord
    Dim o As Object

    ' Iterate through the collection of trace records and write 
    ' them to the response stream.
    Response.Write("<table>")
    For Each o In e.TraceRecords
        r = CType(o, TraceContextRecord)
        Response.Write(String.Format("<tr><td>{0}</td><td>{1}</td></tr>", r.Message, r.Category))
    Next
    Response.Write("</table>")

End Sub ' OnTraceFinished
</script>

.NET Framework
Available since 1.1
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