Visual Basic .NET Language
Test unitario in VB.NET

Osservazioni

Test unitario per il calcolo delle tasse

Questo esempio è diviso in due pilastri

• SalaryCalculation Class : calcolo dello stipendio netto al netto delle detrazioni fiscali
• Classe SalaryCalculationTests : per testare il metodo che calcola il salario netto

Passaggio 1: creare la libreria di classi, denominarla libreria salari o qualsiasi nome appropriato. Quindi rinomina la classe in SalaryCalculation

'' '' '' 'Classe per calcoli salariali' '' Classe pubblica Calcolo salariale

    ''' <summary>
    ''' Employee Salary
    ''' </summary>
    Public Shared Salary As Double

    ''' <summary>
    ''' Tax fraction (0-1)
    ''' </summary>
    Public Shared Tax As Double

    ''' <summary>
    ''' Function to calculate Net Salary
    ''' </summary>
    ''' <returns></returns>
    Public Shared Function CalculateNetSalary()
        Return Salary - Salary * Tax
    End Function
End Class

Passaggio 2 : creare un progetto di test unitario. Aggiungi riferimento alla libreria di classi creata e incolla il codice seguente

Imports WagesLibrary 'Class library you want to test

''' <summary>
''' Test class for testing SalaryCalculation
''' </summary>
<TestClass()> Public Class SalaryCalculationTests

    ''' <summary>
    ''' Test case for the method CalculateNetSalary
    ''' </summary>
    <TestMethod()> Public Sub CalculateNetSalaryTest()
        SalaryCalculation.Salary = 100
        SalaryCalculation.Tax = 0.1
        Assert.AreEqual(90.0, SalaryCalculation.CalculateNetSalary(), 0.1)
    End Sub
End Class

Assert.Equal controlla il valore previsto rispetto al valore calcolato effettivo. il valore 0.1 viene utilizzato per consentire la tolleranza o la variazione tra il risultato previsto e quello effettivo .

Passaggio 3: eseguire il test del metodo per vedere il risultato

Risultato del test

Test delle proprietà assegnate e derivate dalla classe dipendente

Questo esempio ha più test disponibili nei test unitari.

Employee.vb (Class Library)

''' <summary>
''' Employee Class
''' </summary>
Public Class Employee

    ''' <summary>
    ''' First name of employee
    ''' </summary>
    Public Property FirstName As String = ""

    ''' <summary>
    ''' Last name of employee
    ''' </summary>
    Public Property LastName As String = ""

    ''' <summary>
    ''' Full name of employee
    ''' </summary>
    Public ReadOnly Property FullName As String = ""

    ''' <summary>
    ''' Employee's age
    ''' </summary>
    Public Property Age As Byte

    ''' <summary>
    ''' Instantiate new instance of employee
    ''' </summary>
    ''' <param name="firstName">Employee first name</param>
    ''' <param name="lastName">Employee last name</param>
    Public Sub New(firstName As String, lastName As String, dateofbirth As Date)
        Me.FirstName = firstName
        Me.LastName = lastName
        FullName = Me.FirstName + " " + Me.LastName
        Age = Convert.ToByte(Date.Now.Year - dateofbirth.Year)
    End Sub
End Class

EmployeeTest.vb (Test Project)

Imports HumanResources

<TestClass()>
Public Class EmployeeTests
    ReadOnly _person1 As New Employee("Waleed", "El-Badry", New DateTime(1980, 8, 22))
    ReadOnly _person2 As New Employee("Waleed", "El-Badry", New DateTime(1980, 8, 22))

    <TestMethod>
    Public Sub TestFirstName()
        Assert.AreEqual("Waleed", _person1.FirstName, "First Name Mismatch")
    End Sub

    <TestMethod>
    Public Sub TestLastName()
        Assert.AreNotEqual("", _person1.LastName, "No Last Name Inserted!")
    End Sub

    <TestMethod>
    Public Sub TestFullName()
        Assert.AreEqual("Waleed El-Badry", _person1.FullName, "Error in concatination of names")
    End Sub

    <TestMethod>
    Public Sub TestAge()
        Assert.Fail("Age is not even tested !") 'Force test to fail !
        Assert.AreEqual(Convert.ToByte(36), _person1.Age)
    End Sub

    <TestMethod>
    Public Sub TestObjectReference()
        Assert.AreSame(_person1.FullName, _person2.FullName, "Different objects with same data")
    End Sub
End Class

Risultato dopo aver eseguito i test