TraceContextRecord.Message 属性

定义

命名空间:

System.Web

程序集:

System.Web.dll

获取用户定义的跟踪消息。

public:
 property System::String ^ Message { System::String ^ get(); };

public string Message { get; }

member this.Message : string

Public ReadOnly Property Message As String

属性值

String

表示跟踪记录的消息的字符串。

示例

下面的代码示例演示如何访问 Message 的 TraceContextRecord属性，并将其打印到流中 Response 。

<%@ Page language="c#" Trace="true" %>
<script runat="server">
void Page_Load(object sender, EventArgs e)
{
    // Register a handler for the TraceFinished event.
    Trace.TraceFinished += new 
        TraceContextEventHandler(this.OnTraceFinished);

    try {
        throw new ArgumentException("Trace Test");
    }
    catch (InvalidOperationException ioe) {    
        // You can write an error trace message using the Write method.
        Trace.Write("Exception Handling", "Exception: Page_Load.", ioe);
    }
    catch (ArgumentException ae) {    
        // You can write a warning trace message using the Warn method.
        Trace.Warn("Exception Handling", "Warning: Page_Load.", ae);
    }
}
 
// A TraceContextEventHandler for the TraceFinished event.
void OnTraceFinished(object sender, TraceContextEventArgs e)
{
    TraceContextRecord r = null;    
    
    // Iterate through the collection of trace records and write 
    // them to the response stream.
    foreach(object o in e.TraceRecords)
    { 
        r = (TraceContextRecord)o;
        if (r.IsWarning) {
            Response.Write(String.Format("warning message: {0} <BR>", r.Message));
        }
        else {
            Response.Write(String.Format("error message: {0} <BR>", r.Message));
        }

    }
}       
</script>

<%@ 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

    Try 
    Dim ae As New ArgumentException("Trace Test")
        Throw ae
    
    catch ioe As InvalidOperationException
        ' You can write an error trace message using the Write method.
        Trace.Write("Exception Handling", "Exception: Page_Load.", ioe)
    
    Catch ae As ArgumentException
        ' You can write a warning trace message using the Warn method.
        Trace.Warn("Exception Handling", "Warning: Page_Load.", ae)

    End Try

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.

    For Each o In e.TraceRecords
        r = CType(o, TraceContextRecord)
    If r.IsWarning Then
            Response.Write(String.Format("warning message: {0} <BR>", r.Message))
        Else
            Response.Write(String.Format("error message: {0} <BR>", r.Message))
        End If
    Next

End Sub	' OnTraceFinished
</script>

注解

消息可以是任何字符串，用于写入详细的跟踪信息。 它对应于传递给 TraceContext.Write 和 TraceContext.Warn 方法的消息参数。 这些信息可以是运行时值、用于定向并指导你完成程序执行的消息或其他诊断数据。

另请参阅

• ASP.NET 跟踪概述