Question

关于VB声明的问题

　　Declare Function GetVolumeInformation Lib "kernel32" Alias "GetVolumeInformationA"　　(ByVal lpRootPathName As String, ByVal lpVolumeNameBuffer As String, ByVal　　nVolumeNameSize As Long, lpVolumeSerialNumber As Long, lpMaximumComponentLength As　　Long, lpFileSystemFlags As Long, ByVal lpFileSystemNameBuffer As String, ByVal　　nFileSystemNameSize As Long) As Long　　Global GetVal As Long 上面这段话是什么意思 请明白的大虾帮我解释一下 谢谢

Answer 1

上面这段是一个声明该声明的详细介绍GetVolumeInformation
　　VB声明
　　Declare Function GetVolumeInformation Lib "kernel32" Alias "GetVolumeInformationA" (ByVal lpRootPathName As String, ByVal lpVolumeNameBuffer As String, ByVal nVolumeNameSize As Long, lpVolumeSerialNumber As Long, lpMaximumComponentLength As Long, lpFileSystemFlags As Long, ByVal lpFileSystemNameBuffer As String, ByVal nFileSystemNameSize As Long) As Long
　　说明
　　获取与一个磁盘卷有关的信息
　　返回值
　　Long，非零表示成功，零表示失败。会设置GetLastError
　　参数表
　　参数 类型及说明
　　lpRootPathName String，欲获取信息的那个卷的根路径
　　lpVolumeNameBuffer String，用于装载卷名（卷标）的一个字串
　　nVolumeNameSize Long，lpVolumeNameBuffer字串的长度
　　lpVolumeSerialNumber Long，用于装载磁盘卷序列号的变量
　　lpMaximumComponentLength Long，指定一个变量，用于装载文件名每一部分的长度。例如，在“c:\component1\component2.ext”的情况下，它就代表component1或component2名称的长度
　　lpFileSystemFlags Long，用于装载一个或多个二进制位标志的变量。对这些标志位的解释如下：
　　FS_CASE_IS_PRESERVED 文件名的大小写记录于文件系统
　　FS_CASE_SENSITIVE 文件名要区分大小写
　　FS_UNICODE_STORED_ON_DISK 文件名保存为Unicode格式
　　FS_PERSISTANT_ACLS 文件系统支持文件的访问控制列表（ACL）安全机制
　　FS_FILE_COMPRESSION 文件系统支持逐文件的进行文件压缩
　　FS_VOL_IS_COMPRESSED 整个磁盘卷都是压缩的
　　lpFileSystemNameBuffer String，指定一个缓冲区，用于装载文件系统的名称（如FAT，NTFS以及其他）
　　nFileSystemNameSize Long，lpFileSystemNameBuffer字串的长度 以上来自百度百科 Const MOVEFILE_REPLACE_EXISTING = &H1
Const FILE_ATTRIBUTE_TEMPORARY = &H100
Const FILE_BEGIN = 0
Const FILE_SHARE_READ = &H1
Const FILE_SHARE_WRITE = &H2
Const CREATE_NEW = 1
Const OPEN_EXISTING = 3
Const GENERIC_READ = &H80000000
Const GENERIC_WRITE = &H40000000
Private Declare Function SetVolumeLabel Lib "kernel32" Alias "SetVolumeLabelA" (ByVal lpRootPathName As String, ByVal lpVolumeName As String) As Long
Private Declare Function WriteFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToWrite As Long, lpNumberOfBytesWritten As Long, ByVal lpOverlapped As Any) As Long
Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, ByVal lpOverlapped As Any) As Long
Private Declare Function CreateFile Lib "kernel32" Alias "CreateFileA" (ByVal lpFileName As String, ByVal dwDesiredAccess As Long, ByVal dwShareMode As Long, ByVal lpSecurityAttributes As Any, ByVal dwCreationDisposition As Long, ByVal dwFlagsAndAttributes As Long, ByVal hTemplateFile As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function SetFilePointer Lib "kernel32" (ByVal hFile As Long, ByVal lDistanceToMove As Long, lpDistanceToMoveHigh As Long, ByVal dwMoveMethod As Long) As Long
Private Declare Function SetFileAttributes Lib "kernel32" Alias "SetFileAttributesA" (ByVal lpFileName As String, ByVal dwFileAttributes As Long) As Long
Private Declare Function GetFileSize Lib "kernel32" (ByVal hFile As Long, lpFileSizeHigh As Long) As Long
Private Declare Function GetTempFileName Lib "kernel32" Alias "GetTempFileNameA" (ByVal lpszPath As String, ByVal lpPrefixString As String, ByVal wUnique As Long, ByVal lpTempFileName As String) As Long
Private Declare Function MoveFileEx Lib "kernel32" Alias "MoveFileExA" (ByVal lpExistingFileName As String, ByVal lpNewFileName As String, ByVal dwFlags As Long) As Long
Private Declare Function DeleteFile Lib "kernel32" Alias "DeleteFileA" (ByVal lpFileName As String) As Long
Private Sub Form_Load()
Dim sSave As String, hOrgFile As Long, hNewFile As Long, bBytes() As Byte
Dim sTemp As String, nSize As Long, Ret As Long
'Ask for a new volume label
sSave = InputBox("Please enter a new volume label for drive C:\" + vbCrLf + " (if you don't want to change it, leave the textbox blank)")
If sSave <> "" Then
SetVolumeLabel "C:\", sSave
End If
'Create a buffer
sTemp = String(260, 0)
'Get a temporary filename
GetTempFileName "C:\", "KPD", 0, sTemp
'Remove all the unnecessary chr$(0)'s
sTemp = Left$(sTemp, InStr(1, sTemp, Chr$(0)) - 1)
'Set the file attributes
SetFileAttributes sTemp, FILE_ATTRIBUTE_TEMPORARY
'Open the files
hNewFile = CreateFile(sTemp, GENERIC_WRITE, FILE_SHARE_READ Or FILE_SHARE_WRITE, ByVal 0&, OPEN_EXISTING, 0, 0)
hOrgFile = CreateFile("c:\config.sys", GENERIC_READ, FILE_SHARE_READ Or FILE_SHARE_WRITE, ByVal 0&, OPEN_EXISTING, 0, 0)
'Get the file size
nSize = GetFileSize(hOrgFile, 0)
'Set the file pointer
SetFilePointer hOrgFile, Int(nSize / 2), 0, FILE_BEGIN
'Create an array of bytes
ReDim bBytes(1 To nSize - Int(nSize / 2)) As Byte
'Read from the file
ReadFile hOrgFile, bBytes(1), UBound(bBytes), Ret, ByVal 0&
'Check for errors
If Ret <> UBound(bBytes) Then MsgBox "Error reading file ..."
'Write to the file
WriteFile hNewFile, bBytes(1), UBound(bBytes), Ret, ByVal 0&
'Check for errors
If Ret <> UBound(bBytes) Then MsgBox "Error writing file ..."
'Close the files
CloseHandle hOrgFile
CloseHandle hNewFile
'Move the file
MoveFileEx sTemp, "C:\KPDTEST.TST", MOVEFILE_REPLACE_EXISTING
'Delete the file
DeleteFile "C:\KPDTEST.TST"
Unload Me
End Sub 以上是一些例子 你可以下载一个api函数浏览器 就可以产看相关的api 等