в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

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2010-05-26T12:53:51Z

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==Add object to Dictionary==

<source lang="vbnet">Option Strict On
Imports System.Collections.Generic
Public Module modMain
Private employees As Dictionary(Of String, Employee)
Public Sub Main()
employees = New Dictionary(Of String, Employee)
employees.Add("name",New Employee("name", "1"))
employees.Add("name1",New Employee("name1", "1"))
Console.WriteLine("There are {0} employees now on file. They are:",employees.Count)
For Each pair As KeyValuePair(Of String, Employee) In Employees
Console.WriteLine(" {0}: {1}", pair.Key, pair.Value.Name)
Next
End Sub

End Module
Public Class Employee
Private empName As String
Private empID As String
Public Sub New(name As String, ID As String)
Me.empName = name
Me.empID = ID
End Sub
Public Property Name() As String
Get
Return Me.empName
End Get
Set
Me.empName = Value
End Set
End Property
Public Property ID As String
Get
return Me.empID
End Get
Set
Me.empID = Value
End Set
End Property
End Class</source>
<pre class=codeResult>There are 2 employees now on file. They are:
name: name
name1: name1</pre>

==Delete a Directory==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Directory.Delete("c:\\a")
End Sub
End Class</source>

==Delete a directory containing files and sub directories==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Try
System.IO.Directory.Delete("c:\a", True)
Catch ex As Exception
Console.WriteLine(ex.ToString)
Finally
Beep()
End Try

End Sub
End Class</source>

==Delete a directory with exception catch==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Try
System.IO.Directory.Delete("c:\a")
Catch ex As Exception
Console.WriteLine(ex.ToString)
Finally
Beep()
End Try

End Sub
End Class</source>
<pre class=codeResult>System.IO.IOException: The directory is not empty.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.Directory.DeleteHelper(String fullPath, String userPath, Boolean recursive)
at System.IO.Directory.Delete(String fullPath, String userPath, Boolean recursive)
at Tester.Main()</pre>

==Dictionary(Of String, String)==

<source lang="vbnet">Imports System.Collections.Generic
Public Class GenericTest
Public Shared Sub Main()
Dim education As New Dictionary(Of String, String)
education.Add("BA", "Bachelor of Arts")
education.Add("BS", "Bachelor of Science")
education.Add("MA", "Master of Arts")
education.Add("MS", "Master of Science")
education.Add("MPhil", "Master of Philosophy")
education.Add("PhD", "Doctor of Philosophy")
Console.WriteLine(education.Item("BS"))
Console.WriteLine()
For Each pair As KeyValuePair(Of String, String) In education
Console.WriteLine(pair.Value)
Next
End Sub
End Class</source>
<pre class=codeResult>Bachelor of Science
Bachelor of Arts
Bachelor of Science
Master of Arts
Master of Science
Master of Philosophy
Doctor of Philosophy</pre>

==Directory Exists==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

If Directory.Exists("C:\\a") = True Then
Console.WriteLine("true")
End If
End Sub
End Class</source>

==Directory.GetFileSystemEntries==

<source lang="vbnet">Imports System.IO
public class Test
public Shared Sub Main
Dim aryItems() As String
Dim strPath As String = "C:\Program Files"
Dim strItem As String
aryItems = Directory.GetFileSystemEntries(strPath)
For Each strItem In aryItems
If Directory.Exists(strItem) Then
Console.WriteLine("FOLDER " & strItem)
Else
Console.WriteLine("FILE " & strItem)
End If
Next strItem
End Sub
End class</source>
<pre class=codeResult>FOLDER C:\Program Files\Adobe
FOLDER C:\Program Files\AMD
FOLDER C:\Program Files\ATI Technologies
FOLDER C:\Program Files\Common Files
FOLDER C:\Program Files\ComPlus Applications
FOLDER C:\Program Files\CONEXANT
FOLDER C:\Program Files\ftp
FOLDER C:\Program Files\HPQ
FOLDER C:\Program Files\InstallShield Installation Information
FOLDER C:\Program Files\Internet Explorer
FOLDER C:\Program Files\Messenger
FOLDER C:\Program Files\microsoft frontpage
FOLDER C:\Program Files\Microsoft Office</pre>

==Directory Move==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Directory.Move("c:\\b", "c:\\a")

End Sub
End Class</source>

==Get all directories under a directory==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main
Dim arrDirs() As String
Dim strDir As String
Try
arrDirs = Directory.GetDirectories("c:\\")
For Each strDir In arrDirs
Console.WriteLine(strDir)
Next
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
End Class</source>
<pre class=codeResult>c:\\Documents and Settings
c:\\Java_Dev
c:\\oracle
c:\\Program Files
c:\\RECYCLER
c:\\System Volume Information
c:\\SYSTEM.SAV
c:\\Temp
c:\\WINDOWS</pre>

==Get all directories under a directory with conditions==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main
Dim arrDirs() As String
Dim strDir As String
Try
arrDirs = Directory.GetDirectories("c:\\","Wind*")
For Each strDir In arrDirs
Console.WriteLine(strDir)
Next
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
End Class</source>
<pre class=codeResult>c:\\WINDOWS</pre>

==Get all files under a directory==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main
Dim arrDirs() As String
Dim strDir As String
Try
arrDirs = Directory.GetFiles("c:\\")
For Each strDir In arrDirs
Console.WriteLine(strDir)
Next
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
End Class</source>
<pre class=codeResult>c:\\AUTOEXEC.BAT
c:\\boot.ini
c:\\CONFIG.SYS
c:\\DebugMessages.txt
c:\\hiberfil.sys
c:\\IO.SYS
c:\\MSDOS.SYS
c:\\NTDETECT.ru
c:\\ntldr
c:\\pagefile.sys
c:\\test.txt
c:\\test1.txt</pre>

==Get all files under a directory with conditions==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main
Dim arrDirs() As String
Dim strDir As String
Try
arrDirs = Directory.GetFiles("c:\\","*.sys")
For Each strDir In arrDirs
Console.WriteLine(strDir)
Next
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
End Sub
End Class</source>
<pre class=codeResult>c:\\CONFIG.SYS
c:\\hiberfil.sys
c:\\IO.SYS
c:\\MSDOS.SYS
c:\\pagefile.sys</pre>

==Get and set the current directory==

<source lang="vbnet">Imports System.IO
public class Test
public Shared Sub Main
Console.WriteLine("Current directory is " & Directory.GetCurrentDirectory & ".")
Try
Directory.SetCurrentDirectory("..\..\..\..\..\Temp")
Console.WriteLine("Switched current folder to " & _
Directory.GetCurrentDirectory & ".")
Catch exc As FileNotFoundException
Console.WriteLine("Invalid folder specified, currrent directory is " & _
vbCrLf & Directory.GetCurrentDirectory & ".")
Catch exc As Exception
Console.WriteLine("Can"t access the specified folder.")
End Try
End Sub
End class</source>
<pre class=codeResult>Current directory is C:\Java_Dev\WEB\dev\VB.
Switched current folder to C:\Temp.</pre>

==Get current directory: CurDir()==

<source lang="vbnet">Option Strict On
Public Class FileSystemTest
Public Shared Sub Main()
Console.WriteLine(CurDir())
End Sub
End Class</source>
<pre class=codeResult>C:\Java_Dev\WEB\dev\VB</pre>

==Get Directory Root==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Console.WriteLine(Directory.GetDirectoryRoot("c:\\Java_Dev"))
End Sub
End Class</source>
<pre class=codeResult>c:\</pre>

==Get Parent Directory==

<source lang="vbnet">Imports System.IO
Public Class Tester
Public Shared Sub Main

Console.WriteLine(Directory.GetParent("c:\\Java_Dev").ToString)
End Sub
End Class</source>
<pre class=codeResult>c:\</pre>

==Illustrate the pattern of using the Dir function. It is not intended to be compiled.==

<source lang="vbnet">Option Strict On
Public Module modErr
Public Sub Main()
Dim filename As String
filename = Dir("*.*", FileAttribute.Normal)
Do While Not filename = String.Empty
Console.WriteLine(filename)
filename = Dir()
Loop
End Sub
End Module</source>

==String and custom class Dictionary==

<source lang="vbnet">Imports System.Collections.Generic
Public Structure Employee
Dim Name As String
Dim HireDate As Date
Dim BirthDate As Date
End Structure
Public Module Test
Public Sub Main()
Dim employees As New Dictionary(of String, Employee)
Dim dateToFind As Date
Dim input As String
Dim emp As New Employee
emp.Name = "S"
emp.HireDate = #1/2/2003#
emp.BirthDate = #7/12/1977#
employees.Add(emp.Name, emp)
emp.Name = "A"
emp.HireDate = #8/18/1999#
emp.BirthDate = #3/16/1964#
employees.Add(emp.Name, emp)
emp.Name = "B"
emp.HireDate = #3/1/1987#
emp.BirthDate = #11/12/1955#
employees.Add(emp.Name, emp)

dateToFind = CDate("7/12/1977")
For Each employee As KeyValuePair(of String, Employee) In employees
If Month(employee.Value.BirthDate) = Month(dateToFind) AndAlso Day(employee.Value.BirthDate) = Day(dateToFind) Then
Console.WriteLine("{0:MMMM d} is the bithday of {1}.", dateToFind, employee.Key)
End If

If Month(employee.Value.HireDate) = Month(dateToFind) AndAlso Day(employee.Value.HireDate) = Day(dateToFind) Then
Console.WriteLine("{0:MMMM d} is the hiring anniversary of {1}.", dateToFind, employee.Key)
End If
Next
End Sub
End Module</source>

==Use directories match==

<source lang="vbnet">Imports System.IO
public class Test
public Shared Sub Main
Dim aryDirs() As String
Dim strDir As String
aryDirs = Directory.GetDirectories("C:\Windows", "*SYSTEM*")
Console.WriteLine(" folders match the pattern "*SYSTEM*".")
For Each strDir In aryDirs
Console.WriteLine(strDir)
Next strDir
End Sub
End class</source>
<pre class=codeResult>folders match the pattern "*SYSTEM*".
C:\Windows\system
C:\Windows\system32</pre>

==Use MkDir to create a Directory==

<source lang="vbnet">Public Class Tester
Public Shared Sub Main

MkDir("c:\\a")

End Sub
End Class</source>

==Use RmDir to delete a directory==

<source lang="vbnet">Public Class Tester
Public Shared Sub Main

RmDir("c:\\a")
End Sub
End Class</source>

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VB.Net Tutorial/Collections/Dictionary - История изменений

в 16:40, 26 мая 2010

Admin: 1 версия