Visual Basic Scripting Edition | 语言参考 |
在本节描述的示例代码,提供真实的例子来示范在 FileSystemObject 对象模式中可用的许多功能。该代码显示了如何一起使用对象模式的所有功能,以及如何在您自己的代码中有效地使用这些功能。
请注意,由于该代码是极一般的,所以要使该代码能够真正在您的机器上运行,可能需要一些其他代码和小小的变更。这些改变之所以必要,是因为在 Active Server Pages 和 Windows Scripting Host 之间,为输入和输出给用户采用了不同的方法。
要在 Active Server Pages 上运行该代码,则采取以下步骤:
创建一个标准的 Web 页,后缀名为 .asp。
把下面的示例代码复制到 <BODY>...</BODY> 标记之间的文件中。
把所有代码包装器到 <%...%> 标记内。
把 Option Explicit 语句从当前位置移动到 HTML 页的最顶部,甚至在 <HTML> 开始标记前。
把 <%...%> 标记放置在 Option Explicit 语句周围,以保证它在服务器端运行。
把下面的代码添加到示例代码末尾:
Sub Print(x)
Response.Write "<PRE><FONT FACE=""
宋体"" SIZE=""1"">"
Response.Write x
Response.Write "</FONT></PRE>"
End Sub
Main
前面的代码增加一个将在服务器端运行,但在客户端显示结果的打印过程。要在 Windows Scripting Host 上运行该代码,则把下面的代码添加到示例代码的末尾:
Sub Print(x)
WScript.Echo x
End Sub
Main
下面就是示例代码:
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' ' FileSystemObject
示例代码'Copyright 1998 Microsoft Corporation
。 保留所有权利。
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Option Explicit
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
对于代码质量:' 1)
下面的代码有许多字符串操作,用"&"
运算符来把短字符串连接在一起。由于'
字符串连接是费时的,所以这是一种低效率的写代码方法。无论如何,它是'
一种非常好维护的写代码方法,并且在这儿使用了这种方法,因为该程序执行'
大量的磁盘操作,而磁盘操作比连接字符串所需的内存操作要慢得多。'
记住这是示范代码,而不是产品代码。'
' 2)
使用了"Option Explicit"
,因为访问声明过的变量,比访问未声明的变量要'
稍微快一些。它还能阻止在代码中发生错误,例如,把DriveTypeCDROM
误拼'
成了DriveTypeCDORM
。'
' 3)
为了使代码更可读,该代码中没有错误处理。虽然采取了防范措施,来保证代码'
在普通情况下没有错误,但文件系统是不可预知的。在产品代码中,使用' On Error Resume Next
和Err
对象来捕获可能发生的错误。''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
一些容易取得的全局变量''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Dim TabStop
Dim NewLine
Const TestDrive = "C"
Const TestFilePath = "C:\Test"
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
由Drive.DriveType
返回的常数''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Const DriveTypeRemovable = 1
Const DriveTypeFixed = 2
Const DriveTypeNetwork = 3
Const DriveTypeCDROM = 4
Const DriveTypeRAMDisk = 5
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
由File.Attributes
返回的常数''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Const FileAttrNormal = 0
Const FileAttrReadOnly = 1
Const FileAttrHidden = 2
Const FileAttrSystem = 4
Const FileAttrVolume = 8
Const FileAttrDirectory = 16
Const FileAttrArchive = 32
Const FileAttrAlias = 64
Const FileAttrCompressed = 128
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
用来打开文件的常数''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Const OpenFileForReading = 1
Const OpenFileForWriting = 2
Const OpenFileForAppending = 8
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' ShowDriveType
'
目的:
'
生成一个字符串,来描述给定Drive
对象的驱动器类型。'
示范下面的内容' - Drive.DriveType
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function ShowDriveType(Drive)
Dim S
Select Case Drive.DriveType
Case DriveTypeRemovable
S = "Removable"
Case DriveTypeFixed
S = "Fixed"
Case DriveTypeNetwork
S = "Network"
Case DriveTypeCDROM
S = "CD-ROM"
Case DriveTypeRAMDisk
S = "RAM Disk"
Case Else
S = "Unknown"
End Select
ShowDriveType = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' ShowFileAttr
'
目的:
'
生成一个字符串,来描述文件或文件夹的属性。'
示范下面的内容' - File.Attributes
' - Folder.Attributes
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function ShowFileAttr(File) ' File
可以是文件或文件夹Dim S
Dim Attr
Attr = File.Attributes
If Attr = 0 Then
ShowFileAttr = "Normal"
Exit Function
End If
If Attr And FileAttrDirectory Then S = S & "Directory "
If Attr And FileAttrReadOnly Then S = S & "Read-Only "
If Attr And FileAttrHidden Then S = S & "Hidden "
If Attr And FileAttrSystem Then S = S & "System "
If Attr And FileAttrVolume Then S = S & "Volume "
If Attr And FileAttrArchive Then S = S & "Archive "
If Attr And FileAttrAlias Then S = S & "Alias "
If Attr And FileAttrCompressed Then S = S & "Compressed "
ShowFileAttr = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GenerateDriveInformation
'
目的:
'
生成一个字符串,来描述可用驱动器的当前状态。'
示范下面的内容' - FileSystemObject.Drives
' - Iterating the Drives collection
' - Drives.Count
' - Drive.AvailableSpace
' - Drive.DriveLetter
' - Drive.DriveType
' - Drive.FileSystem
' - Drive.FreeSpace
' - Drive.IsReady
' - Drive.Path
' - Drive.SerialNumber
' - Drive.ShareName
' - Drive.TotalSize
' - Drive.VolumeName
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GenerateDriveInformation(FSO)
Dim Drives
Dim Drive
Dim S
Set Drives = FSO.Drives
S = "Number of drives:" & TabStop & Drives.Count & NewLine & NewLine
'
构造报告的第一行。S = S & String(2, TabStop) & "Drive"
S = S & String(3, TabStop) & "File"
S = S & TabStop & "Total"
S = S & TabStop & "Free"
S = S & TabStop & "Available"
S = S & TabStop & "Serial" & NewLine
'
构造报告的第二行。S = S & "Letter"
S = S & TabStop & "Path"
S = S & TabStop & "Type"
S = S & TabStop & "Ready?"
S = S & TabStop & "Name"
S = S & TabStop & "System"
S = S & TabStop & "Space"
S = S & TabStop & "Space"
S = S & TabStop & "Space"
S = S & TabStop & "Number" & NewLine
'
分隔行。S = S & String(105, "-") & NewLine
For Each Drive In Drives
S = S & Drive.DriveLetter
S = S & TabStop & Drive.Path
S = S & TabStop & ShowDriveType(Drive)
S = S & TabStop & Drive.IsReady
If Drive.IsReady Then
If DriveTypeNetwork = Drive.DriveType Then
S = S & TabStop & Drive.ShareName
Else
S = S & TabStop & Drive.VolumeName
End If
S = S & TabStop & Drive.FileSystem
S = S & TabStop & Drive.TotalSize
S = S & TabStop & Drive.FreeSpace
S = S & TabStop & Drive.AvailableSpace
S = S & TabStop & Hex(Drive.SerialNumber)
End If
S = S & NewLine
Next
GenerateDriveInformation = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GenerateFileInformation
'
目的:
'
生成一个字符串,来描述文件的当前状态。'
示范下面的内容' - File.Path
' - File.Name
' - File.Type
' - File.DateCreated
' - File.DateLastAccessed
' - File.DateLastModified
' - File.Size
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GenerateFileInformation(File)
Dim S
S = NewLine & "Path:" & TabStop & File.Path
S = S & NewLine & "Name:" & TabStop & File.Name
S = S & NewLine & "Type:" & TabStop & File.Type
S = S & NewLine & "Attribs:" & TabStop & ShowFileAttr(File)
S = S & NewLine & "Created:" & TabStop & File.DateCreated
S = S & NewLine & "Accessed:" & TabStop & File.DateLastAccessed
S = S & NewLine & "Modified:" & TabStop & File.DateLastModified
S = S & NewLine & "Size" & TabStop & File.Size & NewLine
GenerateFileInformation = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GenerateFolderInformation
'
目的:
'
生成一个字符串,来描述文件夹的当前状态。'
示范下面的内容' - Folder.Path
' - Folder.Name
' - Folder.DateCreated
' - Folder.DateLastAccessed
' - Folder.DateLastModified
' - Folder.Size
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GenerateFolderInformation(Folder)
Dim S
S = "Path:" & TabStop & Folder.Path
S = S & NewLine & "Name:" & TabStop & Folder.Name
S = S & NewLine & "Attribs:" & TabStop & ShowFileAttr(Folder)
S = S & NewLine & "Created:" & TabStop & Folder.DateCreated
S = S & NewLine & "Accessed:" & TabStop & Folder.DateLastAccessed
S = S & NewLine & "Modified:" & TabStop & Folder.DateLastModified
S = S & NewLine & "Size:" & TabStop & Folder.Size & NewLine
GenerateFolderInformation = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GenerateAllFolderInformation
'
目的:
'
生成一个字符串,来描述一个文件夹和所有文件及子文件夹的当前状态。'
示范下面的内容' - Folder.Path
' - Folder.SubFolders
' - Folders.Count
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GenerateAllFolderInformation(Folder)
Dim S
Dim SubFolders
Dim SubFolder
Dim Files
Dim File
S = "Folder:" & TabStop & Folder.Path & NewLine & NewLine
Set Files = Folder.Files
If 1 = Files.Count Then
S = S & "There is 1 file" & NewLine
Else
S = S & "There are " & Files.Count & " files" & NewLine
End If
If Files.Count <> 0 Then
For Each File In Files
S = S & GenerateFileInformation(File)
Next
End If
Set SubFolders = Folder.SubFolders
If 1 = SubFolders.Count Then
S = S & NewLine & "There is 1 sub folder" & NewLine & NewLine
Else
S = S & NewLine & "There are " & SubFolders.Count & " sub folders" & NewLine & NewLine
End If
If SubFolders.Count <> 0 Then
For Each SubFolder In SubFolders
S = S & GenerateFolderInformation(SubFolder)
Next
S = S & NewLine
For Each SubFolder In SubFolders
S = S & GenerateAllFolderInformation(SubFolder)
Next
End If
GenerateAllFolderInformation = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GenerateTestInformation
'
目的:
'
生成一个字符串,来描述C:\Test
文件夹和所有文件及子文件夹的当前状态。'
示范下面的内容' - FileSystemObject.DriveExists
' - FileSystemObject.FolderExists
' - FileSystemObject.GetFolder
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GenerateTestInformation(FSO)
Dim TestFolder
Dim S
If Not FSO.DriveExists(TestDrive) Then Exit Function
If Not FSO.FolderExists(TestFilePath) Then Exit Function
Set TestFolder = FSO.GetFolder(TestFilePath)
GenerateTestInformation = GenerateAllFolderInformation(TestFolder)
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' DeleteTestDirectory
'
目的:
'
清理test
目录。'
示范下面的内容' - FileSystemObject.GetFolder
' - FileSystemObject.DeleteFile
' - FileSystemObject.DeleteFolder
' - Folder.Delete
' - File.Delete
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Sub DeleteTestDirectory(FSO)
Dim TestFolder
Dim SubFolder
Dim File
'
有两种方法可用来删除文件:FSO.DeleteFile(TestFilePath & "\Beatles\OctopusGarden.txt")
Set File = FSO.GetFile(TestFilePath & "\Beatles\BathroomWindow.txt")
File.Delete
'
有两种方法可用来删除文件夹:FSO.DeleteFolder(TestFilePath & "\Beatles")
FSO.DeleteFile(TestFilePath & "\ReadMe.txt")
Set TestFolder = FSO.GetFolder(TestFilePath)
TestFolder.Delete
End Sub
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' CreateLyrics
'
目的:
'
在文件夹中创建两个文本文件。'
示范下面的内容' - FileSystemObject.CreateTextFile
' - TextStream.WriteLine
' - TextStream.Write
' - TextStream.WriteBlankLines
' - TextStream.Close
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Sub CreateLyrics(Folder)
Dim TextStream
Set TextStream = Folder.CreateTextFile("OctopusGarden.txt")
TextStream.Write("Octopus' Garden ") '
请注意,该语句不添加换行到文件中。TextStream.WriteLine("(by Ringo Starr)")
TextStream.WriteBlankLines(1)
TextStream.WriteLine("I'd like to be under the sea in an octopus' garden in the shade,")
TextStream.WriteLine("He'd let us in, knows where we've been -- in his octopus' garden in the shade.")
TextStream.WriteBlankLines(2)
TextStream.Close
Set TextStream = Folder.CreateTextFile("BathroomWindow.txt")
TextStream.WriteLine("She Came In Through The Bathroom Window (by Lennon/McCartney)")
TextStream.WriteLine("")
TextStream.WriteLine("She came in through the bathroom window protected by a silver spoon")
TextStream.WriteLine("But now she sucks her thumb and wanders by the banks of her own lagoon")
TextStream.WriteBlankLines(2)
TextStream.Close
End Sub
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' GetLyrics
'
目的:
'
显示lyrics
文件的内容。'
示范下面的内容' - FileSystemObject.OpenTextFile
' - FileSystemObject.GetFile
' - TextStream.ReadAll
' - TextStream.Close
' - File.OpenAsTextStream
' - TextStream.AtEndOfStream
' - TextStream.ReadLine
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function GetLyrics(FSO)
Dim TextStream
Dim S
Dim File
'
有多种方法可用来打开一个文本文件,和多种方法来从文件读取数据。'
这儿用了两种方法来打开文件和读取文件:Set TextStream = FSO.OpenTextFile(TestFilePath & "\Beatles\OctopusGarden.txt", OpenFileForReading)
S = TextStream.ReadAll & NewLine & NewLine
TextStream.Close
Set File = FSO.GetFile(TestFilePath & "\Beatles\BathroomWindow.txt")
Set TextStream = File.OpenAsTextStream(OpenFileForReading)
Do
While Not TextStream.AtEndOfStream
S = S & TextStream.ReadLine & NewLine
Loop
TextStream.Close
GetLyrics = S
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' BuildTestDirectory
'
目的:
'
创建一个目录分层结构来示范FileSystemObject
。'
以这样的次序来创建分层结构:' C:\Test
' C:\Test\ReadMe.txt
' C:\Test\Beatles
' C:\Test\Beatles\OctopusGarden.txt
' C:\Test\Beatles\BathroomWindow.txt
'
示范下面的内容' - FileSystemObject.DriveExists
' - FileSystemObject.FolderExists
' - FileSystemObject.CreateFolder
' - FileSystemObject.CreateTextFile
' - Folders.Add
' - Folder.CreateTextFile
' - TextStream.WriteLine
' - TextStream.Close
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Function BuildTestDirectory(FSO)
Dim TestFolder
Dim SubFolders
Dim SubFolder
Dim TextStream
'
排除(a)
驱动器不存在,或(b)
要创建的目录已经存在的情况。If Not FSO.DriveExists(TestDrive) Then
BuildTestDirectory = False
Exit Function
End If
If FSO.FolderExists(TestFilePath) Then
BuildTestDirectory = False
Exit Function
End If
Set TestFolder = FSO.CreateFolder(TestFilePath)
Set TextStream = FSO.CreateTextFile(TestFilePath & "\ReadMe.txt")
TextStream.WriteLine("My song lyrics collection")
TextStream.Close
Set SubFolders = TestFolder.SubFolders
Set SubFolder = SubFolders.Add("Beatles")
CreateLyrics SubFolder
BuildTestDirectory = True
End Function
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'
主程序'
首先,它创建一个test
目录,以及一些子文件夹和文件。
'
然后,它转储有关可用磁盘驱动器和test
目录的某些信息,'
最后,清除test
目录及其所有内容。''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Sub Main
Dim FSO
'
设立全局变量。TabStop = Chr(9)
NewLine = Chr(10)
Set FSO = CreateObject("Scripting.FileSystemObject")
If Not BuildTestDirectory(FSO) Then
Print "Test directory already exists or cannot be created. Cannot continue."
Exit Sub
End If
Print GenerateDriveInformation(FSO) & NewLine & NewLine
Print GenerateTestInformation(FSO) & NewLine & NewLine
Print GetLyrics(FSO) & NewLine & NewLine
DeleteTestDirectory(FSO)
End Sub