vb的几个过程语句需要解释
这个帖子以前发过,但问题没彻底解决,我把实在不清楚的理了一下,并加注了标示,更有针对性.为了热心的回帖者更好的解答,将有关的代码全部帖上.走过路过的都来回一下,一个字:急!'代替指定的串
'从一个源串(rStr)中寻找到 子串(vSource)，然后用目标串（vDes）代替子串(vSource)
Private Sub subReplaceStr(ByRef rStr As String, ByVal vSource As String, _
ByVal vDes As String)
Dim i As Integer
On Error Resume Next
If Len(vSource) = 0 Or Len(rStr) = 0 Then Exit Sub
i = 1
i = InStr(i, rStr, vSource)
Do While i > 0
rStr = Left(rStr, i - 1) & vDes & Right(rStr, Len(rStr) - i - Len(vSource) + 1)
i = InStr(i + Len(vDes), rStr, vSource)
DoEvents: DoEvents: DoEvents
Loop
End Sub
'解释参数
'参数存储在para.dat中
Private Sub subPara(ByVal vStr As String)
Dim tCmd As String
Dim tStr As String
Dim i As Long
Dim j As Long
On Error Resume Next
If vStr = "" Then Exit Sub
If Right(vStr, 2) = vbCrLf Then vStr = Left(vStr, Len(vStr) - 2)
tCmd = vStr
j = 1: i = InStr(j, tCmd, ",")
Do While i > 0
tStr = Mid$(tCmd, j, i - j)
funCmdLine tStr
j = i + 1: i = InStr(j, tCmd, ",")
Loop
tStr = Right(tCmd, Len(tCmd) - j + 1)
funCmdLine tStr
End Sub
'解释命令行参数 vStr：传递来的参数，一般为Command
Private Function funCmdLine(ByVal vStr As String) As Byte
Dim i As Integer
Dim tLeft As String
On Error GoTo ErrPos
funCmdLine = 0
DoEvents: DoEvents: DoEvents: DoEvents
vStr = Trim(vStr) ': subReplaceStr vStr, vbTab, ""
If vStr = "" Then Exit Function
i = InStr(vStr, "=")
If i > 0 Then tLeft = Left(vStr, i - 1): vStr = Right(vStr, Len(vStr) - i) Else tLeft = vStr: vStr = ""
tLeft = Trim(tLeft): vStr = Trim(vStr)
Select Case LCase(tLeft)
Case "txtsfile": txtSFile.Text = vStr
Case "txtdfile": txtDFile.Text = vStr
End Select
Exit Function
ErrPos:
subDealError "funCmdLine," & vStr & ",Code:" & Err & ";Descr:" & Error
End Function
'快速读入文本文件
Private Function funReadFile(ByVal vFileName As String) As String
Dim tFileNum As Long
Dim tF As String
Dim tL As Long
Dim tByte() As Byte
On Error GoTo DealError
funReadFile = "": tF = ""
If Dir(vFileName) = "" Then
subDealError "不能找到 " & vFileName & " ！"
Exit Function
End If
tL = FileLen(vFileName): ReDim tByte(1 To tL)
tFileNum = FreeFile
Open vFileName For Binary Access Read As tFileNum （Binary Access Read 方式打开文件方式没见过，表示什么意思？）
Get tFileNum, , tByte
Close tFileNum: DoEvents
tF = StrConv(tByte, vbUnicode) （此函数不懂，不知道有什么作用？）
funReadFile = tF
Exit Function
DealError:
'MsgBox "注意：读文件" & vFileName & "出错，不能取得相关信息！", 48
subDealError "ReadFile " & vFileName & ",Code:" & Err & ",Descr:" & Error （Err和Error 是什么东西？）
On Error Resume Next
Close tFileNum
End Function
'统一处理错误，记入日志文件
Private Sub subDealError(ByVal vStr As String)
Dim tStr As String
Static sI As Integer
On Error Resume Next
If Len(vStr) > 0 Then
lblNote.Caption = vStr: DoEvents
sI = sI + 1
mError = mError & CStr(Now) & "," & vStr & vbCrLf
End If
If (sI = 50 Or Len(vStr) = 0) And Len(mError) > 0 Then
tStr = App.Path & "\log.txt"
subSaveTextFile mError, tStr, True
mError = "": sI = 0
End If
End Sub
'窗体载入部分的代码
Private Sub Form_Load()
Dim tStr As String
Dim tB(-7 To 14) As Byte
Dim i As Integer
On Error Resume Next
m_FXJ_PRP3_RecBytes = 36
'取系统参数
tB(-7) = 33: tB(-6) = 61: tB(-5) = 36: tB(-4) = 46: tB(-3) = 45: tB(-2) = 46: tB(-1) = 54: tB(0) = 32
tB(1) = 88: tB(2) = 89: tB(3) = 90: tB(4) = 50
tB(5) = 92: tB(6) = 89: tB(7) = 91: tB(8) = 87: tB(9) = 76: tB(10) = 85
tB(11) = 57: tB(12) = 90: tB(13) = 82: tB(14) = 98
tStr = ""
For i = -7 To 14: tStr = tStr & Chr$(tB(i) - i): Next
lblWStock.Caption = tStr
tStr = ""
For i = 1 To 14: tStr = tStr & Chr$(tB(i) - i): Next
lblWStock.Tag = tStr （lblWStock是Label ,Tag是表示他的属性吗，是什么含义？）
'解释存储的参数
tStr = App.Path & "\wsPara.dat"
If Dir(tStr) <> "" Then
tStr = funReadFile(tStr)
subPara tStr
End If
tStr = Command （Command是什么？）
If Len(tStr) > 0 Then
subPara tStr
End If
End Sub
'程序退出时的代码
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer) （这是个什么过程，Cancel 和 UnloadMode 变量有什么含义）
Dim tStr As String
Dim i As Integer
On Error Resume Next
If cmdExit.Enabled Then
If Len(Command) = 0 Then '带参数启动不存储参数
tStr = "txtSFile=" & txtSFile.Text & ",txtDFile=" & txtDFile.Text
subSaveTextFile tStr, App.Path & "\wsPara.dat", False
End If
subDealError "" '强制保存日志文件
End
Else
Cancel = 1
End If
End Sub
'统一存储文本文件
' 2001/03/21
Private Sub subSaveTextFile(ByRef rStr As String, ByRef rFileName As String, ByVal vAppend As Boolean)
Dim tFileNum As Long
Dim i As Long
Dim tC As Byte
Dim tPos As Long
Dim tRnd As Integer
Dim tErrDescr As String
On Error GoTo ErrPos
tC = 1
tFileNum = FreeFile
If vAppend Then
If Dir(rFileName) = "" Then tPos = 1 Else tPos = FileLen(rFileName) + 1
Else
If Dir(rFileName) <> "" Then
Kill rFileName: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents
DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents: DoEvents
End If
If Dir(rFileName) <> "" Then '延时，等待删除
For i = 1 To 10000: DoEvents: DoEvents: DoEvents: DoEvents: Next
End If
tPos = 1
End If
Open rFileName For Binary Access Write Lock Write As tFileNum
DoEvents: DoEvents: DoEvents
Put #tFileNum, tPos, rStr
DoEvents: DoEvents: DoEvents
Close tFileNum
DoEvents: DoEvents: DoEvents
Exit Sub
ErrPos:
i = Err: tErrDescr = Error
On Error Resume Next
If i = 70 Then 'Code: 70，Descr：拒绝的权限
'经实际测试，12000次下述循环需要时间为2秒左右
Randomize: tRnd = Int((3000 * Rnd) + 3000) '3000-6000
For i = 0 To tRnd: DoEvents: DoEvents: DoEvents: Next '延时，以保证另外一个程序结束存盘后释放文件写锁
tC = tC + 1
If tC < 30 Then Resume
End If
tC = tC - 1
mError = mError & CStr(Now) & ",SaveTextFile：" & rFileName & ", Resume:" & CStr(tC) & ", Code: " & CStr(i) & "，Descr：" & tErrDescr & vbCrLf
Close tFileNum
End Sub
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