1． 使用VB.Net或C#建立一个Asp.net Web Application。
    2． 在WebForm1.aspx中的代码替换为以下代码：
    Visual Basic .NET Sample

＜%@ Page Language="vb" AutoEventWireup="true" %＞
＜%@ Import namespace="System.Diagnostics" %＞
＜!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"＞
＜HTML＞
＜script language="VB" runat="server"＞
Sub WriteEvent_Click(Src As Object, e As EventArgs)
Dim ev As New EventLog("Application")
' Event's Source name
ev.Source = "TEST"

EventLog.CreateEventSource(ev.Source, "Application")

Try
ev.WriteEntry(TextBox1.Text)
Catch b as exception
Response.write ("WriteEntry " & b.message & "＜br＞")
End Try
ev = Nothing
End Sub
＜/script＞

＜body＞
＜form id="Form1" runat="server"＞
Event message:
＜asp:textbox id="TextBox1" runat="server" Width="233px"＞＜/asp:textbox＞
＜asp:button id="Button1" onclick="WriteEvent_Click" runat="server" NAME="Button1" text="Write to event log"＞＜/asp:button＞
＜/form＞
＜/body＞
＜/HTML＞ 

    Visual C# .NET Sample

＜%@ Page Language="c#" AutoEventWireup="true" %＞
＜%@ Import namespace="System.Diagnostics" %＞
＜!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"＞
＜HTML＞
＜script language="C#" runat="server"＞
void WriteEvent_Click(Object Src, EventArgs e)
{
EventLog ev = new EventLog("Application");
// Event's Source name
ev.Source = "TEST";

EventLog.CreateEventSource(ev.Source, "Application");

try
{
ev.WriteEntry(TextBox1.Text);
}
catch (Exception b)
{
Response.Write("WriteEntry " + b.Message + "＜br＞");
}
ev = null;
}
＜/script＞

＜body＞
＜form id="Form1" runat="server"＞
Event message:
＜asp:textbox id="TextBox1" runat="server" Width="233px"＞＜/asp:textbox＞
＜asp:button id="Button1" onclick="WriteEvent_Click" runat="server" NAME="Button1" text="Write to event log"＞＜/asp:button＞
＜/form＞
＜/body＞
＜/HTML＞

    3． 按F5启动此项目。
    4． 在TextBox输入一些字符，然后点击Write to Event Log。
    5． 在上面“现象”部分中提到的错误消息会出现。
    6． 要解决此问题，在Webform1.aspx将下面这行代码注释

EventLog.CreateEventSource(ev.Source, "Application"); 

    7． 重新启动此项目。