Simple Error Reporting

This should be a no-brainer, but every ASP.NET application you put out there should have some solid error reporting behind it. The simplest way you can do this is by sending an email message each time there is an error. Nothing like debugging an error before the customer even contacts you about it. Code below.

You'll want to put the following in your Global.asax file:

VB.NET:

Sub Application_Error(ByVal sender As Object, ByVal e As EventArgs)

    If Request.ServerVariables("server_name") <> "localhost" AndAlso InStr(Request.Url.ToString, "get_aspx_ver.aspx") = 0 AndAlso InStr(Request.Url.ToString.ToLower(), "webresource.axd") = 0 AndAlso InStr(Request.Url.ToString.ToLower(), "scriptresource.axd") = 0 Then
    
        ' only run this if it's NOT the localhost and it's a real error - don't care about webresource.axd or scriptresource.axd errors since those don't usually show themselves to the end user

        Dim objErr As Exception = Server.GetLastError.GetBaseException

        Dim err As String

        err = "<p><b>Error caught in Application_Error event:</b></p>"
        err = err & "<p>Error URL: " & Request.Url.ToString & "</p>"
        err = err & "<p>Error Message: " & objErr.Message.ToString & "</p>"
        err = err & "<p>Source: " & objErr.Source.ToString & "</p>"
        err = err & "<p>Stack Trace: " & objErr.StackTrace.ToString & "</p>"
        err = err & "<p>Client IP Address: " & Request.ServerVariables("REMOTE_ADDR") & "</p>"

        Server.ClearError()


        Dim objMail As System.Net.Mail.SmtpClient = New System.Net.Mail.SmtpClient("your.smtp.server")
        Dim mailFrom As System.Net.Mail.MailAddress = New System.Net.Mail.MailAddress("from@somewhere.com", "Error")
        Dim mailTo As System.Net.Mail.MailAddress = New System.Net.Mail.MailAddress("to@somewhere.com")
        Dim mailMsg As System.Net.Mail.MailMessage = New System.Net.Mail.MailMessage(mailFrom, mailTo)
        mailMsg.Subject = "Error"

        mailMsg.Body = err
        mailMsg.IsBodyHtml = True
        objMail.Send(mailMsg)

        ' redirect to a friendly error page
        Response.Redirect("~/Error.htm")

    End If

End Sub

C#:

void Application_Error(object sender, EventArgs e) 
{ 
    // Code that runs when an unhandled error occurs

    string url = Request.Url.ToString();

    if (Request.ServerVariables["server_name"] != "localhost" && url.IndexOf("get_aspx_ver.aspx", 0) == -1 && url.IndexOf("WebResource.axd", 0) == -1 && url.IndexOf("ScriptResource.axd", 0) == -1)
    {
        Exception objErr = Server.GetLastError().GetBaseException();

        string err = "<p><b>Error caught in Application_Error event:</b></p>";
        err += "<p>Error URL: " + Request.Url.ToString() + "</p>";
        err += "<p>Error Message: " + objErr.Message.ToString() + "</p>";
        err += "<p>Source: " + objErr.Source.ToString() + "</p>";
        err += "<p>Stack Trace: " + objErr.StackTrace.ToString() + "</p>";
        err += "<p>Client IP Address: " + Request.ServerVariables["remote_addr"].ToString() + "</p>";

        Server.ClearError();

        ' add your own email code here
        
        Response.Redirect("~/Error.htm");
    }
}