如何：为 Web 性能测试创建自定义验证规则
您可以创建自己的验证规则。 若要实现此目的，可以从某个验证规则类派生自己的规则类。 验证规则从 ValidationRule 基类派生。
Visual Studio 旗舰版 提供了一些预定义的验证规则。 有关更多信息，请参见在 Web 性能测试中使用验证规则和提取规则。
备注
也可以创建自定义提取规则。有关更多信息，请参见为负载和 Web 性能测试创建和使用自定义插件。
要求
- Visual Studio 旗舰版
创建自定义验证规则
打开一个包含 Web 性能测试的测试项目。
（可选）创建一个将在其中存储验证规则的单独的类库项目。
重要
您可以在测试所在的项目中创建类。但是，如果您希望重用规则，则最好创建一个单独的类库项目来存储规则。如果创建单独的项目，则必须完成本过程中的可选步骤。
（可选）在该类库项目中，添加一个对 Microsoft.VisualStudio.QualityTools.WebTestFramework DLL 的引用。
创建一个从 ValidationRule 类派生的类。 实现 Validate 和 RuleName 成员。
（可选）生成新的类库项目。
（可选）在测试项目中添加一个对包含自定义验证规则的类库项目的引用。
在测试项目中的**“Web 性能测试编辑器”**中打开一个 Web 性能测试。
若要将自定义验证规则添加到 Web 性能测试请求中，请右击请求并选择**“添加验证规则”**。
将出现**“添加验证规则”对话框。 您将在“选择规则”**列表中看到您的自定义验证规则以及预定义的验证规则。 选择您的自定义验证规则然后选择 确定。
运行该 Web 性能测试。
示例
下面的代码演示如何实现自定义验证规则。 此验证规则模仿预定义的“所需的标记”验证规则的行为。 可基于该示例创建您自己的自定义验证规则。
using System;
using System.Diagnostics;
using System.Globalization;
using Microsoft.VisualStudio.TestTools.WebTesting;
namespace SampleWebTestRules
{
//-------------------------------------------------------------------------
// This class creates a custom validation rule named "Custom Validate Tag"
// The custom validation rule is used to check that an HTML tag with a
// particular name is found one or more times in the HTML response.
// The user of the rule can specify the HTML tag to look for, and the
// number of times that it must appear in the response.
//-------------------------------------------------------------------------
public class CustomValidateTag : ValidationRule
{
/// Specify a name for use in the user interface.
/// The user sees this name in the Add Validation dialog box.
//---------------------------------------------------------------------
public override string RuleName
{
get { return "Custom Validate Tag"; }
}
/// Specify a description for use in the user interface.
/// The user sees this description in the Add Validation dialog box.
//---------------------------------------------------------------------
public override string RuleDescription
{
get { return "Validates that the specified tag exists on the page."; }
}
// The name of the required tag
private string RequiredTagNameValue;
public string RequiredTagName
{
get { return RequiredTagNameValue; }
set { RequiredTagNameValue = value; }
}
// The minimum number of times the tag must appear in the response
private int MinOccurrencesValue;
public int MinOccurrences
{
get { return MinOccurrencesValue; }
set { MinOccurrencesValue = value; }
}
// Validate is called with the test case Context and the request context.
// These allow the rule to examine both the request and the response.
//---------------------------------------------------------------------
public override void Validate(object sender, ValidationEventArgs e)
{
bool validated = false;
int numTagsFound = 0;
foreach (HtmlTag tag in e.Response.HtmlDocument.GetFilteredHtmlTags(RequiredTagName))
{
Debug.Assert(string.Equals(tag.Name, RequiredTagName, StringComparison.InvariantCultureIgnoreCase));
if (++numTagsFound >= MinOccurrences)
{
validated = true;
break;
}
}
e.IsValid = validated;
// If the validation fails, set the error text that the user sees
if (!validated)
{
if (numTagsFound > 0)
{
e.Message = String.Format("Only found {0} occurences of the tag", numTagsFound);
}
else
{
e.Message = String.Format("Did not find any occurences of tag '{0}'", RequiredTagName);
}
}
}
}
}
Imports System
Imports System.Diagnostics
Imports System.Globalization
Imports Microsoft.VisualStudio.TestTools.WebTesting
Namespace SampleWebTestRules
'-------------------------------------------------------------------------
' This class creates a custom validation rule named "Custom Validate Tag"
' The custom validation rule is used to check that an HTML tag with a
' particular name is found one or more times in the HTML response.
' The user of the rule can specify the HTML tag to look for, and the
' number of times that it must appear in the response.
'-------------------------------------------------------------------------
Public Class CustomValidateTag
Inherits Microsoft.VisualStudio.TestTools.WebTesting.ValidationRule
' Specify a name for use in the user interface.
' The user sees this name in the Add Validation dialog box.
'---------------------------------------------------------------------
Public Overrides ReadOnly Property RuleName() As String
Get
Return "Custom Validate Tag"
End Get
End Property
' Specify a description for use in the user interface.
' The user sees this description in the Add Validation dialog box.
'---------------------------------------------------------------------
Public Overrides ReadOnly Property RuleDescription() As String
Get
Return "Validates that the specified tag exists on the page."
End Get
End Property
' The name of the required tag
Private RequiredTagNameValue As String
Public Property RequiredTagName() As String
Get
Return RequiredTagNameValue
End Get
Set(ByVal value As String)
RequiredTagNameValue = value
End Set
End Property
' The minimum number of times the tag must appear in the response
Private MinOccurrencesValue As Integer
Public Property MinOccurrences() As Integer
Get
Return MinOccurrencesValue
End Get
Set(ByVal value As Integer)
MinOccurrencesValue = value
End Set
End Property
' Validate is called with the test case Context and the request context.
' These allow the rule to examine both the request and the response.
'---------------------------------------------------------------------
Public Overrides Sub Validate(ByVal sender As Object, ByVal e As ValidationEventArgs)
Dim validated As Boolean = False
Dim numTagsFound As Integer = 0
For Each tag As HtmlTag In e.Response.HtmlDocument.GetFilteredHtmlTags(RequiredTagName)
Debug.Assert(String.Equals(tag.Name, RequiredTagName, StringComparison.InvariantCultureIgnoreCase))
numTagsFound += 1
If numTagsFound >= MinOccurrences Then
validated = True
Exit For
End If
Next
e.IsValid = validated
' If the validation fails, set the error text that the user sees
If Not (validated) Then
If numTagsFound > 0 Then
e.Message = String.Format("Only found {0} occurences of the tag", numTagsFound)
Else
e.Message = String.Format("Did not find any occurences of tag '{0}'", RequiredTagName)
End If
End If
End Sub
End Class
End Namespace
请参见
任务
参考
Microsoft.VisualStudio.TestTools.WebTesting.Rules
ValidationRuleRequiredAttributeValue