TraceContextEventHandler 委托

定义

表示处理 TraceFinished 对象的 TraceContext 事件的方法。Represents the method that handles the TraceFinished event of a TraceContext object.

public delegate void TraceContextEventHandler(System::Object ^ sender, TraceContextEventArgs ^ e);
public delegate void TraceContextEventHandler(object sender, TraceContextEventArgs e);
type TraceContextEventHandler = delegate of obj * TraceContextEventArgs -> unit
Public Delegate Sub TraceContextEventHandler(sender As Object, e As TraceContextEventArgs)

参数

sender
Object

事件源 (TraceContext)。The event source (the TraceContext).

e
TraceContextEventArgs

包含事件数据的 TraceContextEventArgsA TraceContextEventArgs that contains the event data.

继承
TraceContextEventHandler

示例

下面的代码示例演示如何注册TraceContextEventHandler委托来TraceFinished处理事件。The following code example demonstrates how to register a TraceContextEventHandler delegate to handle the TraceFinished event. 在此示例中, OnTraceFinished方法循环访问跟踪记录并将它们写入响应流。In this example, the OnTraceFinished method iterates through the trace records and writes them to the response stream.

<%@ 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.
    foreach(object o in e.TraceRecords)
    {
        r = (TraceContextRecord)o;
        Response.Write(String.Format("trace 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

    ' 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.

    For Each o In e.TraceRecords
        r = CType(o, TraceContextRecord)
        Response.Write(String.Format("trace message: {0} <BR>", r.Message))
    Next

End Sub ' OnTraceFinished
</script>

注解

创建 TraceContextEventHandler 委托时,需要标识将处理该事件的方法。When you create a TraceContextEventHandler delegate, you identify the method that will handle the event. 若要将事件与事件处理程序关联,请将该委托的一个实例添加到事件中。To associate the event with your event handler, add an instance of the delegate to the event. 除非移除了该委托,否则每当发生该事件时就会调用事件处理程序。The event handler is called whenever the event occurs, unless you remove the delegate.

有关事件处理程序委托的详细信息, 请参阅处理和引发事件For more information about event handler delegates, see Handling and Raising Events.

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。Gets an object that represents the method represented by the specified delegate.

适用于

另请参阅