作法:建立項目清單
本主題中的程式碼定義 Student
類別並建立此類別的執行個體清單。 此清單旨在支援下列主題:逐步解說:在 Visual Basic 中撰寫查詢。 也可以用於任何需要物件清單的應用程式。 程式碼會使用物件初始設定式來定義學員清單中的項目。
範例
如果您正在執行本逐步解說,可將此程式碼使用於在其中建立之專案的 Module1.vb 檔案。 使用本逐步解說中所提供的查詢和查詢執行,取代 Main
中標示 **** 的程式行。
Module Module1
Sub Main()
' Create a list of students.
Dim students = GetStudents()
' Display the names in the list.
DisplayList(students)
' ****Paste query and query execution code from the walkthrough,
' ****or any code of your own, here in Main.
Console.ReadLine()
End Sub
' Call DisplayList to see the names of the students in the list.
' You can expand this method to see other student properties.
Sub DisplayList(ByVal studentCol As IEnumerable(Of Student))
For Each st As Student In studentCol
Console.WriteLine("First Name: " & st.First)
Console.WriteLine(" Last Name: " & st.Last)
Console.WriteLine()
Next
End Sub
' Function GetStudents returns a list of Student objects.
Function GetStudents() As IEnumerable(Of Student)
Return New List(Of Student) From
{
New Student("Michael", "Tucker", "Junior", 10),
New Student("Svetlana", "Omelchenko", "Senior", 2),
New Student("Michiko", "Osada", "Senior", 7),
New Student("Sven", "Mortensen", "Freshman", 53),
New Student("Hugo", "Garcia", "Junior", 16),
New Student("Cesar", "Garcia", "Freshman", 4),
New Student("Fadi", "Fakhouri", "Senior", 72),
New Student("Hanying", "Feng", "Senior", 11),
New Student("Debra", "Garcia", "Junior", 41),
New Student("Lance", "Tucker", "Junior", 60),
New Student("Terry", "Adams", "Senior", 6)
}
End Function
' Each student has a first name, a last name, a class year, and
' a rank that indicates academic ranking in the student body.
Public Class Student
Public Property First As String
Public Property Last As String
Public Property Year As String
Public Property Rank As Integer
Public Sub New()
End Sub
Public Sub New(ByVal firstName As String,
ByVal lastName As String,
ByVal studentYear As String,
ByVal studentRank As Integer)
First = firstName
Last = lastName
Year = studentYear
Rank = studentRank
End Sub
End Class
End Module