ExtractionRule::Extract Method (Object^, ExtractionEventArgs^)
When overridden in a derived class, this method extracts information from a HtmlDocument and places it into the WebTestContext.
Assembly: Microsoft.VisualStudio.QualityTools.WebTestFramework (in Microsoft.VisualStudio.QualityTools.WebTestFramework.dll)
Parameters
- sender
-
Type:
System::Object^
The source of the event.
- e
-
Type:
Microsoft.VisualStudio.TestTools.WebTesting::ExtractionEventArgs^
An ExtractionEventArgs that contains the event data.
This method contains the core extraction functionality. This method has the responsibility of extracting the data from the response.
Notes to Inheritors:
When overridden in a derived class, the Extract method adds the extracted value to the WebTestContext provided by e.WebTest.Context. The name for the value added to the WebTestContext is set with the ContextParameterName property. If the extraction is a success, e.Success is set to true; otherwise it should be set to false.
Legacy Code Example
The following is a Web performance test that uses the ExtractCheckBoxes custom extraction rule. The code for this can be found at ExtractionRule. The code checks for the existence of check boxes in the HtmlDocument provided by the WebTestResponse that is contained in the ExtractionEventArgs. The results are yielded to the test engine.
namespace TestProject1 { using System; using System.Collections.Generic; using Microsoft.VisualStudio.TestTools.WebTesting; using ClassLibrary2; public class MyWebTest : WebTest { public MyWebTest() { this.PreAuthenticate = true; } public override IEnumerator<WebTestRequest> GetRequestEnumerator() { WebTestRequest request1 = new WebTestRequest("http://localhost/ts"); ExtractCheckBoxes rule1 = new ExtractCheckBoxes(); rule1.FindCheckedBoxes = true; rule1.ContextParameterName = "CheckedBoxes"; request1.ExtractValues += new EventHandler <ExtractionEventArgs>(rule1.Extract); ExtractCheckBoxes rule2 = new ExtractCheckBoxes(); rule2.FindCheckedBoxes = false; rule2.ContextParameterName = ""; request1.ExtractValues += new EventHandler <ExtractionEventArgs>(rule2.Extract); yield return request1; } } }
The following is a coded Web performance test called MyCodedWebTest that inherits from ThreadedWebTest. This test extracts Hidden Fields. The second request posts form information contained within in three controls back to the server.
Option Strict Off Option Explicit On Imports Microsoft.VisualStudio.TestTools.WebTesting Imports Microsoft.VisualStudio.TestTools.WebTesting.Rules Imports System Imports System.Collections.Generic Namespace TestProject2 Public Class MyCodedWebTest Inherits ThreadedWebTest Public Sub New() MyBase.New Me.PreAuthenticate = true Me.Proxy = "myproxy.com:80" End Sub Public Overrides Sub Run() Dim request1 As WebTestRequest = New WebTestRequest _ ("http://localhost/MyWebSite") request1.ThinkTime = 1 Dim rule1 As ExtractHiddenFields = New ExtractHiddenFields rule1.ContextParameterName = "1" AddHandler request1.ExtractValues, AddressOf rule1.Extract MyBase.Send(request1) Dim request2 As WebTestRequest = New WebTestRequest _ ("http://localhost/MyWebSite/Default.aspx") request2.Method = "POST" Dim request2Body As FormPostHttpBody = New FormPostHttpBody request2Body.FormPostParameters.Add("__VIEWSTATE", "{{$HIDDEN1" + _ ".__VIEWSTATE}}") request2Body.FormPostParameters.Add("Button1", "Button") request2Body.FormPostParameters.Add("TextBox1", "Hello text") request2.Body = request2Body Dim rule2 As ExtractHiddenFields = New ExtractHiddenFields rule2.ContextParameterName = "" AddHandler request2.ExtractValues, AddressOf rule2.Extract MyBase.Send(request2) End Sub End Class End Namespace