Measure Web Request Execution Time in C#

To measure web request execution time in C#, create a custom TimeLoggerMessageHandler, use Stopwatch inside the handler, insert it into INetworkService.MessageHandlers, and open the HTML document with that configuration.

Performance diagnostics often require knowing how long a request takes to pass through the HTML loading pipeline. For example, you may need to measure the time required to read a file from the file system or download data from a remote server before deciding whether the workflow needs caching, timeout handling, or request filtering.

Message Handler for Logging the Time of File Loading

Create TimeLoggerMessageHandler

The following code snippet shows how to create a TimeLoggerMessageHandler to log the time taken for reading a file from the file system.

 1// Log request time with custom C# message handler
 2
 3// Define the TimeLoggerMessageHandler class that is derived from the MessageHandler class
 4public class TimeLoggerMessageHandler : MessageHandler
 5{
 6    // Override the Invoke() method
 7    public override void Invoke(INetworkOperationContext context)
 8    {
 9        // Start the stopwatch
10        Stopwatch stopwatch = Stopwatch.StartNew();
11
12        // Invoke the next message handler in the chain
13        Next(context);
14
15        // Stop the stopwatch
16        stopwatch.Stop();
17
18        // Print the result
19        Debug.WriteLine("Request: " + context.Request.RequestUri);
20        Debug.WriteLine("Time: " + stopwatch.ElapsedMilliseconds + "ms");
21    }
22}

Example-TimeLoggerMessageHandler.cs hosted with ❤ by GitHub

Use the Stopwatch class in the System.Diagnostics namespace to measure how long the web request takes. The StartNew() method starts the timer, and Stop() ends measurement after the request has completed.

Add TimeLoggerMessageHandler to the Pipeline

After the handler is implemented, add it to the network pipeline:

Create a Configuration object.
Get the INetworkService instance from the configuration.
Use MessageHandlers.Insert() to place TimeLoggerMessageHandler first in the handler collection.
Open the document with HTMLDocument(address, configuration).
Review the logged loading time.

The Insert() method adds TimeLoggerMessageHandler at the first position in the collection, so the request is measured before later handlers continue processing.

 1// Track HTML load time in C# using a custom network message handler
 2
 3// Create an instance of the Configuration class
 4using Configuration configuration = new Configuration();
 5
 6// Add the TimeLoggerMessageHandler to the chain of existing message handlers
 7INetworkService service = configuration.GetService<INetworkService>();
 8MessageHandlerCollection handlers = service.MessageHandlers;
 9           
10handlers.Insert(0, new TimeLoggerMessageHandler());
11
12// Prepare path to a source document file
13string documentPath = Path.Combine(DataDir, "input.htm");
14
15// Initialize an HTML document with specified configuration
16using HTMLDocument document = new HTMLDocument(documentPath, configuration);

Example-WebRequestExecutionTime.cs hosted with ❤ by GitHub

You can download the complete examples and data files from GitHub.

FAQ

What does this example measure?

It measures how long a web request takes while an HTML document is opened with the configured message handler pipeline.

Why insert the logger at the first position?

Placing the logger first lets it measure the request before later handlers or default processing continue the pipeline.

Can this be combined with timeout handling?

Yes. Use a time logger for diagnostics and a timeout handler when slow or unavailable resources should be interrupted.

Network Timeouts – set maximum operation time for slow remote resources.
Execution Time Logging – combine ZIP resource loading, PDF rendering, and request duration logging.
Message Handler Use Cases in C# – compare common message handler workflows.

Execution Time Logging Authentication