What is ASP.Net tracing

Tracing is a valuable activity that allows developers to track the execution path and retrieve diagnostic information pertaining to a specific Asp.Net web page or application as it runs on the web server. Tracing functionality can be enabled during both the development and production stages of an application. By using tracing, developers can gain valuable insights into errors or unexpected outcomes that may occur during the processing of an ASP.NET page request.

When tracing is enabled, informative details are collected and made available for analysis. These details can aid in the investigation and resolution of issues encountered during the execution of an ASP.NET application. Tracing information can be conveniently accessed at the bottom of individual pages, providing immediate visibility into the execution flow and associated diagnostic data.

Furthermore, ASP.NET offers a trace viewer, which serves as a dedicated tool for inspecting and analyzing the collected trace information. The trace viewer grants developers the ability to examine the cached trace data in a structured and comprehensive manner, empowering them to gain deeper insights into the application's behavior and pinpoint potential areas for improvement or troubleshooting.

In Asp.Net Tracing is disabled by default. Trace statements are executed and shown only when tracing is enabled. You can enabled tracing in two levels.

  1. Page Leve Tracing
  2. Application Level Tracing

You can enabled individual pages as well as you can enabled your application's Web.config file to display trace information. When you enabled it application level, it display all pages trace information unless the page explicitly disables tracing.

Page Leve Tracing

We can control whether tracing is enabled or disabled for an Asp.Net page with the Trace attribute of the @ Page directive.

<%@ Page Trace="true" %> <%@ Page Language="VB" Trace="true" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>

Application Level Tracing

When we enable application level tracing, trace information is gathered and processed for each page in that application. We can enable application level tracing by using the trace element in the Web.config file.

<configuration> <system.web> <trace enabled="true" pageOutput="true" requestLimit="50" localOnly="false" mostRecent="true"traceMode="SortByTime" /> </system.web> </configuration>

By default, application level tracing can be viewed only on the local Web server computer. The above configuration enables an application trace configuration that collects trace information for up to 50 requests.


Enabling tracing and utilizing the trace viewer offers developers a powerful means to diagnose issues, validate the expected behavior of their application, and optimize its performance. By utilizing the capabilities of tracing, developers can enhance the quality and reliability of their ASP.NET web pages and applications.