要以二进制读取一个文件的两个数据块,但是使用FOR感觉速度实在是痛苦~~~,大家有没有什么更快一点的方法~~
解决方案 »
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- 窗体之间切换
比如:添加1个按钮(command1) 2个列表框(list1,list2)
Private Type F
k(1 To 1024) As Byte
End TypePrivate Sub Command1_Click()
Dim f1 As F, x As Integer
With f1
Open "d:\1.dat" For Binary As #1
For x = 1 To 1024
.k(x) = 255 * Rnd
List1.AddItem .k(x)
Next
Put #1, , f1
Close
Open "d:\1.dat" For Binary As #1
Get #1, , f1
Close #1
For x = 1 To 1024
List2.AddItem .k(x)
Next
End With
End Sub
Put #1, , f1
Close
为
Put #1, , f1
Close #1
dim a(1023) as byte,b(2047) as byte
open "c:\input.dat" for binary as #1
get #1,,a
get #1,,b
close #1
''读写文件的类,为文件的读写操作提供了封装,用起来更方便,重用度好
''这是读文件的类。
''刘琦。2005-3-7 Last modified.
''*************************************************************** Private m_bFileOpened As Boolean ''文件打开标志 Private m_iFileNum As Integer ''文件号,为什么用Integer,由FreeFile的定义得知 Private m_lFileLen As Long ''文件长度 Private Declare Sub CopyMemory Lib "kernel32" Alias _
"RtlMoveMemory" (Destination As Any, _
Source As Any, ByVal Length As Long) Public Function OpenBinary(ByVal sFQFilename As String) As Boolean
''打开一个二进制文件,成功返回真,失败返回假
''INPUT------------------------------------------------------------
''sFQFilename 要打开文件的全路径名
''-----------------------------------------------------------------
''OUTPUT-----------------------------------------------------------
''返回值 成功返回真,失败返回假
''-----------------------------------------------------------------
''备注-------------------------------------------------------------
''该类的一个实例在同一时间只能够打开一个文件。
''----------------------------------------------------------------- OpenBinary = False ''default Return value. On Error GoTo catch ''错误捕获 If m_bFileOpened Then Err.Raise 1000 ''如果该类的实例正处在打开文件的
''状态,那么不允许打开另一个文件,引发一个错误。这意味着这个类遵循强严谨
''性编码规则,而非强容错性编码规则(按这个规则的要求,就不会报错,而是自
''动关闭上一个打开的文件) m_iFileNum = FreeFile ''取得一个合法文件号 ''以二进制、只读方式打开文件
Open sFQFilename For Binary Access Read As #m_iFileNum m_bFileOpened = True ''如果能执行到这一句,说明文件打开了,记录状态 m_lFileLen = LOF(m_iFileNum) ''取得文件长度 OpenBinary = True ''return succeed flag!!! Exit Function
catch:
End Function Public Sub CloseFile()
''关闭曾经用OpenBinary打开过的文件 If m_bFileOpened Then ''如果现在正处在打开文件的状态。 ''如果当前状态为有文件打开,那么关闭它,并设置当前状态
Close #m_iFileNum ''关闭文件
m_bFileOpened = False ''文件打开标志设为假
m_iFileNum = -1 ''把文件号和文件长度设为无效值
m_lFileLen = -1
Else
''如果没有打开文件
Err.Raise 1000 ''报错,这意味着这个类遵循强严谨
''性编码规则
End If End Sub
Public Property Get FileNumber() As Integer
FileNumber = m_iFileNum
End Property Public Property Get FileOpened() As Boolean
FileOpened = m_bFileOpened
End Property Public Property Get FileLength() As Long
FileLength = m_lFileLen
End Property
''------------------------------------------------------- Public Function ReadBlock(ByVal lpBuffer As Long, _
ByVal lBufferSize As Long) As Long
''读文件的块,在使用此方法前需要先打开文件
''INPUT------------------------------------------------------------------------------
''lpBuffer 用来接受数据的缓冲区指针
''lBufferSize 指出缓冲区的大小(以字节计)
'' (也就是期望从文件中读取的字节数)
''OUTPUT-----------------------------------------------------------------------------
''返回值 实际读取到缓冲区的字节数,可能等于也可能小于 lBufferSize Dim lTemp As Long
Dim aBuf() As Byte ''计算出从当前文件指针开始到文件末尾还有多少字节未读
''计算方法就是文件长度减去已读的字节数,就是未读的字节数
''就是 m_lFileLen-(seek(m_ifilenum)-1)
lTemp = m_lFileLen - Seek(m_iFileNum) + 1 If lTemp >= lBufferSize Then ''[lBufferSize..)
''未读字节数大于等于缓冲区大小 ''可以填满缓冲区(这种情况的出现概率较大,所以放在最前)
ReadBlock = lBufferSize ''返回实际读取到缓冲区的字节数
ReDim aBuf(0 To lBufferSize - 1) ''分配空间,大小是lBufferSize
Get #m_iFileNum, , aBuf() ''从文件中读取 lBufferSize个字节
CopyMemory ByVal lpBuffer, aBuf(0), lBufferSize
''把数据复制到客户的缓冲区 ElseIf lTemp > 0 Then ''(0..lBufferSize) 也即 [1..lBufferSize-1]
'' 0< lTemp < lBufferSize ''还有字节需要读,但不足以填满缓冲区
ReadBlock = lTemp ''返回实际读取的字节数
ReDim aBuf(0 To lTemp - 1) ''定义一个刚好能容纳将要读取数据的数组
Get #m_iFileNum, , aBuf() ''读块
CopyMemory ByVal lpBuffer, aBuf(0), lTemp ''投放到客户提供的缓冲区里 Else ''( ..0] ''没有字节需要读了,回吧
ReadBlock = 0 ''返回实际读取到缓冲区的字节数 End If End Function Private Sub Class_Terminate()
If m_bFileOpened Then Err.Raise 1000, , "Please Close File"
End Sub
''--------------------------------------------------------------------------------------------------------------------------- ''CFileWrite.cls-------------------------------------------------------------------------------------------------------- Option Explicit ''***************************************************************
''读写文件的类,为文件的读写操作提供了封装,用起来更方便,重用度好
''这是写文件的类。
''刘琦。2005-3-7 Last modified.
''*************************************************************** ''CFileWrite-------------------------------------------------------------------------- Private m_bFileOpened As Boolean ''文件打开标志 Private m_iFileNum As Integer ''文件号,为什么用Integer,由FreeFile的定义得知 Private m_lFileLen As Long ''文件长度 Private Declare Sub CopyMemory Lib "kernel32" Alias _
"RtlMoveMemory" (Destination As Any, Source As Any, _
ByVal Length As Long) Public Function OpenBinary(ByVal sFQFilename As String) As Boolean
''打开一个文件,成功返回真,失败返回假
''INPUT------------------------------------------------------------
''sFQFilename 要打开文件的全路径名
''-----------------------------------------------------------------
''OUTPUT-----------------------------------------------------------
''返回值 成功返回真,失败返回假
''-----------------------------------------------------------------
''备注-------------------------------------------------------------
''该类的一个实例在同一时间只能够打开一个文件。
''----------------------------------------------------------------- OpenBinary = False ''default Return On Error GoTo catch If m_bFileOpened Then Err.Raise 1000 ''如果该类的实例正处在打开文件的
''状态,那么不允许打开另一个文件,引发一个错误。这意味着这个类遵循强严谨
''性编码规则,而非强容错性编码规则(按这个规则的要求,就不会报错,而是自
''动关闭上一个打开的文件) m_iFileNum = FreeFile ''取得一个合法文件号 ''以二进制、只写方式打开文件
Open sFQFilename For Binary Access Write As #m_iFileNum m_bFileOpened = True ''如果能执行到这一句,说明文件打开了,记录状态
m_lFileLen = LOF(m_iFileNum) ''取得文件长度 OpenBinary = True ''return succeed flag!!!
Exit Function
catch:
End Function Public Sub CloseFile()
''关闭曾经用OpenBinary打开过的文件 If m_bFileOpened Then ''如果现在正处在打开文件的状态。 ''如果当前状态为有文件打开,那么关闭它,并设置当前状态
Close #m_iFileNum ''关闭文件
m_bFileOpened = False ''文件打开标志设为假
m_iFileNum = -1 ''把文件号和文件长度设为无效值
m_lFileLen = -1
Else
''如果没有打开文件
Err.Raise 1000 ''报错,这意味着这个类遵循强严谨
''性编码规则
End If End Sub ''只读属性------------------------------------------
Public Property Get FileNumber() As Integer
FileNumber = m_iFileNum
End Property Public Property Get FileOpened() As Boolean
FileOpened = m_bFileOpened
End Property Public Property Get FileLength() As Long
FileLength = m_lFileLen
End Property
''------------------------------------------------------- Public Sub WriteBlock(ByVal lpBuffer As Long, ByVal nCount As Long)
''把一块缓冲区的数据写入到文件中,前提是文件必须打开
''INPUT--------------------------------------------------------------
''lpBuffer 数据缓冲区的指针
''nCount 期望写入的字节数
''OUTPUT-------------------------------------------------------------
''N/A
''
Dim aBuf() As Byte If nCount <= 0 Then Exit Sub ReDim aBuf(0 To nCount - 1) ''定义一个于期望写入的字节数大小相等的数组 CopyMemory aBuf(0), ByVal lpBuffer, nCount ''把客户提供的数据拷贝到aBuf()中 Put #m_iFileNum, , aBuf() ''写到文件 End Sub
If m_bFileOpened Then Err.Raise 1000, , "Please Close File"
End Sub ''---------------------------------------------------------------------------------------------------------------------------- ''以下是使用范例------------------------------------------------------------------------------------------------------- ''form1.frm-------------------------------------------------------------------------------------------------------------- Option Explicit Dim m_cFileRead As New CFileRead
Dim m_cFileWrite As New CFileWrite Private Sub Command1_Click()
Const BUFFER_SIZE As Long = 4096 * 2
Dim nActual As Long
Dim aBuf(0 To BUFFER_SIZE - 1) As Byte
Dim lpBuf As Long
Dim tmr As Single tmr = Timer lpBuf = VarPtr(aBuf(0)) If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text Do
nActual = m_cFileRead.ReadBlock(lpBuf, BUFFER_SIZE)
m_cFileWrite.WriteBlock lpBuf, nActual
Loop Until nActual < BUFFER_SIZE ''当实际读取字节数小于缓冲区大小的时候,就不需要再读啦,已读完啦 m_cFileRead.CloseFile
m_cFileWrite.CloseFile MsgBox "OK! total time:" & Timer - tmr
End Sub Private Sub Command2_Click()
Const BUFFER_SIZE = 1
Dim nActual As Long
Dim aBuf(0 To BUFFER_SIZE - 1) As Byte
Dim tmr As Single tmr = Timer If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text Do
nActual = m_cFileRead.ReadBlock(VarPtr(aBuf(0)), BUFFER_SIZE)
m_cFileWrite.WriteBlock VarPtr(aBuf(0)), nActual
Loop Until nActual < BUFFER_SIZE ''当实际读取字节数小于缓冲区大小的时候,就不需要再读啦,已读完啦 m_cFileRead.CloseFile
m_cFileWrite.CloseFile MsgBox "OK! total time:" & Timer - tmr
End Sub Private Sub Command3_Click()
Const BUFFER_SIZE = 40960 * 2
Dim nActual As Long
Dim aBuf(0 To BUFFER_SIZE - 1) As Byte
Dim tmr As Single
Dim lFileLen As Long
Dim iFileNum As Integer
Dim k As Long tmr = Timer If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text
lFileLen = m_cFileRead.FileLength
iFileNum = m_cFileRead.FileNumber k = 0
Do
k = k + 1
If k = 10 Then
k = 0
pb1.Value = 100 * (Seek(iFileNum) / lFileLen)
DoEvents
End If
nActual = m_cFileRead.ReadBlock(VarPtr(aBuf(0)), BUFFER_SIZE)
m_cFileWrite.WriteBlock VarPtr(aBuf(0)), nActual
Loop Until nActual < BUFFER_SIZE ''当实际读取字节数小于缓冲区大小的时候,就不需要再读啦,已读完啦 m_cFileRead.CloseFile
m_cFileWrite.CloseFile MsgBox "OK! total time:" & Timer - tmr
End Sub Private Sub Command4_Click()
Dim sPass As String
sPass = InputBox("请输入密码。")
Dim cLogi As New CLogistic
cLogi.Pass = sPass Const BUFFER_SIZE = 4096
Dim nActual As Long
Dim aBuf(0 To BUFFER_SIZE - 1) As Byte
Dim tmr As Single
Dim lFileLen As Long
Dim iFileNum As Integer
Dim k As Long tmr = Timer If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text
lFileLen = m_cFileRead.FileLength
iFileNum = m_cFileRead.FileNumber k = 0
Do
k = k + 1
If k = 10 Then
k = 0
pb1.Value = 100 * (Seek(iFileNum) / lFileLen)
DoEvents
End If
nActual = m_cFileRead.ReadBlock(VarPtr(aBuf(0)), BUFFER_SIZE)
cLogi.EncBlock aBuf, nActual
m_cFileWrite.WriteBlock VarPtr(aBuf(0)), nActual
Loop Until nActual < BUFFER_SIZE ''当实际读取字节数小于缓冲区大小的时候,就不需要再读啦,已读完啦 m_cFileRead.CloseFile
m_cFileWrite.CloseFile MsgBox "OK! total time:" & Timer - tmr End Sub Private Sub Command5_Click()
If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
m_cFileRead.CloseFile If Not m_cFileRead.OpenBinary(Text1.Text) Then MsgBox "打开文件失败!" & Text1.Text
m_cFileRead.CloseFile If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text
m_cFileWrite.CloseFile
If Not m_cFileWrite.OpenBinary(Text2.Text) Then MsgBox "打开文件失败!" & Text2.Text
m_cFileWrite.CloseFile End Sub
先seek再get读就好了,不知道有什么问题?
viena(维也纳nn),很久没来了啊谢谢 Modest(塞北雪貂)·(偶最欣赏楼主的分) ,我等下试试