TraceContextRecord.Category 屬性

定義

命名空間:

System.Web

組件:

System.Web.dll

取得追蹤記錄的使用者定義分類。

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

public string Category { get; }

member this.Category : string

Public ReadOnly Property Category As String

屬性值

String

字串，表示追蹤記錄的分類。

範例

下列程式碼範例示範如何存取 Category 的 TraceContextRecord 屬性，並將它及其相關聯的追蹤訊息列印至 Response 資料流程。

<%@ 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);

    // Write a trace message.
    Trace.Write("Web Forms Infrastructure Methods", "USERMESSAGE: Page_Load complete.");
}
 
// 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.
    Response.Write("<table>");
    foreach(object o in e.TraceRecords)
    {
        r = (TraceContextRecord)o;
        Response.Write(String.Format("<tr><td>{0}</td><td>{1}</td></tr>", r.Message, r.Category));        
    }
    Response.Write("</table>");
}       
</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

    ' 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>

備註

類別可用來將追蹤訊息更妥善地組織成可辨識的群組，但可以是任何字串。 類別 TraceContext 會針對只 message 接受參數的方法，使用 String.Empty 做為其預設類別。 啟用追蹤時寫入數筆追蹤記錄的 ASP.NET 預設類別為 「aspx.page」。

另請參閱

• ASP.NET 追蹤概觀