VB.Net by API/System.Collections/hashtable — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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Текущая версия на 12:51, 26 мая 2010
Содержание
Hashtable.Add
Imports System
Imports System.Collections
Public Class MainClass
Public Shared Sub Main()
Dim table As Hashtable = New Hashtable()
Dim employee As New Employee("First Name", "Last Name")
Try
table.Add("Last Name", employee)
Console.WriteLine("Put: " & employee.ToString())
Catch argumentException As ArgumentException
Console.WriteLine(argumentException.ToString())
End Try
Dim result As Object = table("Last Name")
If Not result Is Nothing Then
Console.WriteLine("Get: " & result.ToString())
Else
Console.WriteLine("Get: " & "Last Name" & " not in table")
End If
table.Remove("Last Name")
Console.WriteLine("table count: " & table.Count)
Console.WriteLine("Contains key: " & table.ContainsKey("Last Name"))
table.Clear()
Dim enumerator As IDictionaryEnumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(Convert.ToString(enumerator.Value))
End While
enumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(enumerator.Key )
End While
End Sub
End Class
Public Class Employee
Private firstName, lastName As String
Public Sub New(ByVal first As String, ByVal last As String)
firstName = first
lastName = last
End Sub
Public Overrides Function ToString() As String
Return firstName & " " & lastName
End Function
End Class
Hashtable.GetEnumerator()
Imports System
Imports System.Collections
Public Class MainClass
Public Shared Sub Main()
Dim table As Hashtable = New Hashtable()
Dim employee As New Employee("First Name", "Last Name")
Try
table.Add("Last Name", employee)
Console.WriteLine("Put: " & employee.ToString())
Catch argumentException As ArgumentException
Console.WriteLine(argumentException.ToString())
End Try
Dim result As Object = table("Last Name")
If Not result Is Nothing Then
Console.WriteLine("Get: " & result.ToString())
Else
Console.WriteLine("Get: " & "Last Name" & " not in table")
End If
table.Remove("Last Name")
Console.WriteLine("table count: " & table.Count)
Console.WriteLine("Contains key: " & table.ContainsKey("Last Name"))
table.Clear()
Dim enumerator As IDictionaryEnumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(Convert.ToString(enumerator.Value))
End While
enumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(enumerator.Key )
End While
End Sub
End Class
Public Class Employee
Private firstName, lastName As String
Public Sub New(ByVal first As String, ByVal last As String)
firstName = first
lastName = last
End Sub
Public Overrides Function ToString() As String
Return firstName & " " & lastName
End Function
End Class
Hashtable.Item
Imports System
Imports System.Collections
Class Test
Shared Sub Main()
Dim myTable As New Hashtable()
myTable.Item("A") = 1
myTable.Item("B") = 44
myTable.Item("C") = 43
myTable.Item("D") = 33
myTable.Item("E") = 39
Dim Country As String = "C"
Dim Code As Integer = myTable.Item(Country)
Console.WriteLine(Code)
End Sub
End Class
Hashtable.Keys
Imports System
Imports System.Collections
Imports System.Environment
Public Class MainClass
Shared Sub Main()
Dim eVariables As Hashtable
eVariables = CType(GetEnvironmentVariables(), Hashtable)
Dim thing As Object
For Each thing In eVariables.Keys
Console.WriteLine("The environment variable named " & thing.ToString() _
& " has value " & eVariables(thing).ToString())
Next
End Sub
End Class
Hashtable.Remove
Imports System
Imports System.Collections
Public Class MainClass
Public Shared Sub Main()
Dim table As Hashtable = New Hashtable()
Dim employee As New Employee("First Name", "Last Name")
Try
table.Add("Last Name", employee)
Console.WriteLine("Put: " & employee.ToString())
Catch argumentException As ArgumentException
Console.WriteLine(argumentException.ToString())
End Try
Dim result As Object = table("Last Name")
If Not result Is Nothing Then
Console.WriteLine("Get: " & result.ToString())
Else
Console.WriteLine("Get: " & "Last Name" & " not in table")
End If
table.Remove("Last Name")
Console.WriteLine("table count: " & table.Count)
Console.WriteLine("Contains key: " & table.ContainsKey("Last Name"))
table.Clear()
Dim enumerator As IDictionaryEnumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(Convert.ToString(enumerator.Value))
End While
enumerator = table.GetEnumerator()
While enumerator.MoveNext()
Console.WriteLine(enumerator.Key )
End While
End Sub
End Class
Public Class Employee
Private firstName, lastName As String
Public Sub New(ByVal first As String, ByVal last As String)
firstName = first
lastName = last
End Sub
Public Overrides Function ToString() As String
Return firstName & " " & lastName
End Function
End Class