Automating HttpWatch with Visual Basic

July 23, 2008 in Automation , HttpWatch , Internet Explorer

HttpWatch includes automation samples in C# and in a previous post we used C# to create simple empty cache and primed cache tests. However, a number of customers have recently asked how they can get started with HttpWatch and VB.Net. To use Visual Basic simply follow these steps:

1. Create a VB.Net Project

In Visual Studio create a new console application for Visual Basic:

Create VB.Net Console Application

2. Add a Reference for HttpWatch

To use the COM based HttpWatch automation API you need to create a reference by right clicking on the project and going to ‘Add Reference…’ :

Add Reference

When the ‘Add Reference’ dialog opens click on the COM tab. If you have HttpWatch Basic or Professional Edition installed you should be able to find HttpWatch in the list of COM type libraries. A quick way to do this is to type ‘httpwatch’ into the References dialog. Once you have found the HttpWatch Automation library; select it and click on OK:

HttpWatch COM Reference

3. Start Writing Code!

The HttpWatch automation objects are now available in VB.Net. To make life easier you may want to add an Imports HttpWatch statement into your code so that you don’t have to add the HttpWatch namespace onto the name of every automation class and interface. There’s documentation for the API in the HttpWatch help file and you’ll see Intellisense prompts as you start writing code:

Writing VB.Net for HttpWatch

Here’s an example of a simple program to test how long a page takes to load:

Imports HttpWatch 
Imports System       
 
Module Module1       
 
    Sub Main() 
        Dim url As String = "http://www.httpwatch.com"       
 
        Dim controller As Controller = New Controller       
 
        ' Create a new instance of IE 
        Dim plugin As Plugin = controller.[New]       
 
        plugin.Record() 
        plugin.GotoURL(url)       
 
        ' Wait for page to load 
        controller.Wait(plugin, -1)       
 
        plugin.Stop()       
 
        Dim pageLoadTime As Double = _ 
            plugin.Log.Pages(0).Entries.Summary.Time       
 
        Console.WriteLine("The page loaded in " + _ 
            pageLoadTime.ToString() + " secs")       
 
        plugin.Container.Quit() ' Close IE 
    End Sub       
 
End Module

And here is the empty cache test converted to VB.Net:

 
Imports HttpWatch 
Imports System     
 
Module Module1     
 
    Sub Main() 
        Dim url As String = "http://www.httpwatch.com" 
        Dim controller As Controller = New Controller     
 
        ' Create a new instance of IE 
        Dim plugin As Plugin = controller.[New]     
 
        'Clear out all existing cache entries 
        plugin.ClearCache()     
 
        plugin.Record() 
        plugin.GotoURL(url)     
 
        ' Wait for page to load 
        controller.Wait(plugin, -1)     
 
        plugin.Stop()     
 
        Dim pageLoadTime As Double = _ 
            plugin.Log.Pages(0).Entries.Summary.Time     
 
        Console.WriteLine("The page loaded in " + _ 
            pageLoadTime.ToString() + " secs")     
 
        ' Uncomment the next line to save the results 
        ' plugin.Log.Save("c:\temp\emptycachetest.hwl")     
 
        plugin.Container.Quit() ' Close IE 
    End Sub     
 
End Module

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