dreamweaverMX通用分页代码研究

2019-11-18 20:16:03

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DreamweaverMX已经正式发布了，Deamweaver4 + Deamweaver ULTRADEV 4 的组合使他成为当然的制做网页的首选工具，（好象做广告：）　)
好了，进入正题，
我在以前做网页的分页时候都是用自己写的服务端脚本(我从不用ADO的分页)，用了MX后发现在这里面用分页太方便了，不过代码也有点太长了，大家看下面的代码就可以知道。用过之后我发现里面recordset 的cursortype设为0分页竟然可以正常工作！这令我吃惊不少，分析了代码之后才发现MX 是用了一种挺笨的方法实现的，效率很低，所以大家还是用1吧：）
分析如下:

<%@LANGUAGE="VBSCRipT" CODEPAGE="936"%>

<%
Dim Recordset1
Dim Recordset1_numRows

Set Recordset1 = Server.CreateObject("ADODB.Recordset")
Recordset1.ActiveConnection = MM_ncarcnn_STRING
Recordset1.Source = "SELECT * FROM dbo.ncarinfo"

Recordset1.CursorType = 0
'这里用0也可以正常运行，但是经过分析代码可以看出，用0的效率很低，建议用1

Recordset1.CursorLocation = 2
Recordset1.LockType = 1
Recordset1.Open()

Recordset1_numRows = 0
%>

<%
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'以下为分页代码
Dim Repeat1__numRows
Dim Repeat1__index

Repeat1__numRows = 10
Repeat1__index = 0
Recordset1_numRows = Recordset1_numRows + Repeat1__numRows
%>
<%
'  *** Recordset状态, 定义状态变量

Dim Recordset1_total
Dim Recordset1_first
Dim Recordset1_last

' set the record count
Recordset1_total = Recordset1.RecordCount

' set the number of rows displayed on this page
If (Recordset1_numRows < 0) Then
  Recordset1_numRows = Recordset1_total
Elseif (Recordset1_numRows = 0) Then
  Recordset1_numRows = 1
End If

' set the first and last displayed record
Recordset1_first = 1
Recordset1_last  = Recordset1_first + Recordset1_numRows - 1

' if we have the correct record count, check the other stats 处理正确的rs
If (Recordset1_total <> -1) Then
  If (Recordset1_first > Recordset1_total) Then
    Recordset1_first = Recordset1_total
  End If
  If (Recordset1_last > Recordset1_total) Then
    Recordset1_last = Recordset1_total
  End If
  If (Recordset1_numRows > Recordset1_total) Then
    Recordset1_numRows = Recordset1_total
  End If
End If
%>
<%
' *** Recordset Stats: if we don't know the record count, manually count them处理错误的RS

If (Recordset1_total = -1) Then

  ' count the total records by iterating through the recordset
  Recordset1_total=0
  While (Not Recordset1.EOF)
    Recordset1_total = Recordset1_total + 1
    Recordset1.MoveNext
  Wend

  ' reset the cursor to the beginning
  If (Recordset1.CursorType > 0) Then
    Recordset1.MoveFirst
  Else
    Recordset1.Requery
  End If

  ' set the number of rows displayed on this page
  If (Recordset1_numRows < 0 Or Recordset1_numRows > Recordset1_total) Then
    Recordset1_numRows = Recordset1_total
  End If

  ' set the first and last displayed record
  Recordset1_first = 1
  Recordset1_last = Recordset1_first + Recordset1_numRows - 1

  If (Recordset1_first > Recordset1_total) Then
    Recordset1_first = Recordset1_total
  End If
  If (Recordset1_last > Recordset1_total) Then
    Recordset1_last = Recordset1_total
  End If

End If
%>
<%
Dim MM_paramName
%>
<%
' *** Move To Record and Go To Record: declare variables

Dim MM_rs
Dim MM_rsCount
Dim MM_size
Dim MM_uniqueCol
Dim MM_offset
Dim MM_atTotal
Dim MM_paramIsDefined

Dim MM_param
Dim MM_index

Set MM_rs    = Recordset1
MM_rsCount   = Recordset1_total
MM_size      = Recordset1_numRows
MM_uniqueCol = ""
MM_paramName = ""
MM_offset = 0
MM_atTotal = false
MM_paramIsDefined = false
If (MM_paramName <> "") Then
  MM_paramIsDefined = (Request.QueryString(MM_paramName) <> "")
End If
%>
<%
' *** Move To Record: handle 'index' or 'offset' parameter

if (Not MM_paramIsDefined And MM_rsCount <> 0) then

  ' use index parameter if defined, otherwise use offset parameter
  MM_param = Request.QueryString("index")
  If (MM_param = "") Then
    MM_param = Request.QueryString("offset")
  End If
  If (MM_param <> "") Then
    MM_offset = Int(MM_param)
  End If

  ' if we have a record count, check if we are past the end of the recordset
  If (MM_rsCount <> -1) Then
    If (MM_offset >= MM_rsCount Or MM_offset = -1) Then  ' past end or move last
      If ((MM_rsCount Mod MM_size) > 0) Then         ' last page not a full repeat region
        MM_offset = MM_rsCount - (MM_rsCount Mod MM_size)
      Else
        MM_offset = MM_rsCount - MM_size
      End If
    End If
  End If

  ' move the cursor to the selected record
  MM_index = 0
  While ((Not MM_rs.EOF) And (MM_index < MM_offset Or MM_offset = -1))
    MM_rs.MoveNext
    MM_index = MM_index + 1
  Wend
  If (MM_rs.EOF) Then
    MM_offset = MM_index  ' set MM_offset to the last possible record
  End If

End If
%>
<%
' *** Move To Record: if we dont know the record count, check the display range

If (MM_rsCount = -1) Then

  ' walk to the end of the display range for this page
  MM_index = MM_offset
  While (Not MM_rs.EOF And (MM_size < 0 Or MM_index < MM_offset + MM_size))
    MM_rs.MoveNext
    MM_index = MM_index + 1
  Wend

  ' if we walked off the end of the recordset, set MM_rsCount and MM_size
  If (MM_rs.EOF) Then
    MM_rsCount = MM_index
    If (MM_size < 0 Or MM_size > MM_rsCount) Then
      MM_size = MM_rsCount
    End If
  End If

  ' if we walked off the end, set the offset based on page size
  If (MM_rs.EOF And Not MM_paramIsDefined) Then
    If (MM_offset > MM_rsCount - MM_size Or MM_offset = -1) Then
      If ((MM_rsCount Mod MM_size) > 0) Then
        MM_offset = MM_rsCount - (MM_rsCount Mod MM_size)
      Else
        MM_offset = MM_rsCount - MM_size
      End If
    End If
  End If

  ' reset the cursor to the beginning
  If (MM_rs.CursorType > 0) Then
    MM_rs.MoveFirst
  Else
    MM_rs.Requery
  End If

  ' move the cursor to the selected record
  MM_index = 0
  While (Not MM_rs.EOF And MM_index < MM_offset)
    MM_rs.MoveNext
    MM_index = MM_index + 1
  Wend
End If
%>
<%
' *** Move To Record: update recordset stats

' set the first and last displayed record
Recordset1_first = MM_offset + 1
Recordset1_last  = MM_offset + MM_size

If (MM_rsCount <> -1) Then
  If (Recordset1_first > MM_rsCount) Then
    Recordset1_first = MM_rsCount
  End If
  If (Recordset1_last > MM_rsCount) Then
    Recordset1_last = MM_rsCount
  End If
End If

' set the boolean used by hide region to check if we are on the last record
MM_atTotal = (MM_rsCount <> -1 And MM_offset + MM_size >= MM_rsCount)
%>
<%
' *** Go To Record and Move To Record: create strings for maintaining URL and Form parameters

Dim MM_keepNone
Dim MM_keepURL
Dim MM_keepForm
Dim MM_keepBoth

Dim MM_removeList
Dim MM_item
Dim MM_nextItem

' create the list of parameters which should not be maintained
MM_removeList = "&index="
If (MM_paramName <> "") Then
  MM_removeList = MM_removeList & "&" & MM_paramName & "="
End If

MM_keepURL=""
MM_keepForm=""
MM_keepBoth=""
MM_keepNone=""

' add the URL parameters to the MM_keepURL string
For Each MM_item In Request.QueryString
  MM_nextItem = "&" & MM_item & "="
  If (InStr(1,MM_removeList,MM_nextItem,1) = 0) Then
    MM_keepURL = MM_keepURL & MM_nextItem & Server.URLencode(Request.QueryString(MM_item))
  End If
Next

' add the Form variables to the MM_keepForm string
For Each MM_item In Request.Form
  MM_nextItem = "&" & MM_item & "="
  If (InStr(1,MM_removeList,MM_nextItem,1) = 0) Then
    MM_keepForm = MM_keepForm & MM_nextItem & Server.URLencode(Request.Form(MM_item))
  End If
Next

' create the Form + URL string and remove the intial '&' from each of the strings
MM_keepBoth = MM_keepURL & MM_keepForm
If (MM_keepBoth <> "") Then
  MM_keepBoth = Right(MM_keepBoth, Len(MM_keepBoth) - 1)
End If
If (MM_keepURL <> "")  Then
  MM_keepURL  = Right(MM_keepURL, Len(MM_keepURL) - 1)
End If
If (MM_keepForm <> "") Then
  MM_keepForm = Right(MM_keepForm, Len(MM_keepForm) - 1)
End If

' a utility function used for adding additional parameters to these strings
Function MM_joinChar(firstItem)
  If (firstItem <> "") Then
    MM_joinChar = "&"
  Else
    MM_joinChar = ""
  End If
End Function
%>
<%
' *** Move To Record: set the strings for the first, last, next, and PRevious links

Dim MM_keepMove
Dim MM_moveParam
Dim MM_moveFirst
Dim MM_moveLast
Dim MM_moveNext
Dim MM_movePrev

Dim MM_urlStr
Dim MM_paramList
Dim MM_paramIndex
Dim MM_nextParam

MM_keepMove = MM_keepBoth
MM_moveParam = "index"

' if the page has a repeated region, remove 'offset' from the maintained parameters
If (MM_size > 1) Then
  MM_moveParam = "offset"
  If (MM_keepMove <> "") Then
    MM_paramList = Split(MM_keepMove, "&")
    MM_keepMove = ""
    For MM_paramIndex = 0 To UBound(MM_paramList)
      MM_nextParam = Left(MM_paramList(MM_paramIndex), InStr(MM_paramList(MM_paramIndex),"=") - 1)
      If (StrComp(MM_nextParam,MM_moveParam,1) <> 0) Then
        MM_keepMove = MM_keepMove & "&" & MM_paramList(MM_paramIndex)
      End If
    Next
    If (MM_keepMove <> "") Then
      MM_keepMove = Right(MM_keepMove, Len(MM_keepMove) - 1)
    End If
  End If
End If

' set the strings for the move to links
If (MM_keepMove <> "") Then
  MM_keepMove = MM_keepMove & "&"
End If

MM_urlStr = Request.ServerVariables("URL") & "?" & MM_keepMove & MM_moveParam & "="

MM_moveFirst = MM_urlStr & "0"
MM_moveLast  = MM_urlStr & "-1"
MM_moveNext  = MM_urlStr & CStr(MM_offset + MM_size)
If (MM_offset - MM_size < 0) Then
  MM_movePrev = MM_urlStr & "0"
Else
  MM_movePrev = MM_urlStr & CStr(MM_offset - MM_size)
End If
%>
<html>
<head>
<title>Untitled Document</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head>

<body>
<p></p>

<table border="1">
  <tr>
    <td>cpno</td>
    <td>cbno</td>
    <td>cdpt</td>
    <td>cid</td>
    <td>cbnm</td>
    <td>ddate</td>
    <td>cstate</td>
    <td>guid</td>
  </tr>
  <% While ((Repeat1__numRows <> 0) AND (NOT Recordset1.EOF)) %>
  <tr>
    <td><%=(Recordset1.Fields.Item("cpno").Value)%></td>
    <td><%=(Recordset1.Fields.Item("cbno").Value)%></td>
    <td><%=(Recordset1.Fields.Item("cdpt").Value)%></td>
    <td><%=(Recordset1.Fields.Item("cid").Value)%></td>
    <td><%=(Recordset1.Fields.Item("cbnm").Value)%></td>
    <td><%=(Recordset1.Fields.Item("ddate").Value)%></td>
    <td><%=(Recordset1.Fields.Item("cstate").Value)%></td>
    <td><%=(Recordset1.Fields.Item("guid").Value)%></td>
  </tr>
  <%
  Repeat1__index=Repeat1__index+1
  Repeat1__numRows=Repeat1__numRows-1
  Recordset1.MoveNext()
Wend
%>

</table>
<p> </p>
<table border="0" width="50%" align="center">
  <tr>
    <td width="23%" align="center"> <% If MM_offset <> 0 Then %>
      <a href="<%=MM_moveFirst%>"><img src="First.gif" border=0></a>
      <% End If ' end MM_offset <> 0 %> </td>
    <td width="31%" align="center"> <% If MM_offset <> 0 Then %>
      <a href="<%=MM_movePrev%>"><img src="Previous.gif" border=0></a>
      <% End If ' end MM_offset <> 0 %> </td>
    <td width="23%" align="center"> <% If Not MM_atTotal Then %>
      <a href="<%=MM_moveNext%>"><img src="Next.gif" border=0></a>
      <% End If ' end Not MM_atTotal %> </td>
    <td width="23%" align="center"> <% If Not MM_atTotal Then %>
      <a href="<%=MM_moveLast%>"><img src="Last.gif" border=0></a>
      <% End If ' end Not MM_atTotal %> </td>
  </tr>
</table>

Records <%=(Recordset1_first)%> to <%=(Recordset1_last)%> of <%=(Recordset1_total)%>
</body>
</html>
<%
Recordset1.Close()
Set Recordset1 = Nothing
%>

编译成dll用也可以：）

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