dreamweaverMX通用分页代码研究

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

' *** 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

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

' 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

' *** 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

' 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

' 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

' 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

' 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

' 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

If (MM_keepMove <> "") Then

MM_keepMove = Right(MM_keepMove, Len(MM_keepMove) - 1)

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>

</head>

<body>

<p></p>

<tr>

<td>ddate</td>

<td>cstate</td>

</tr>

<% While ((Repeat1__numRows <> 0) AND (NOT Recordset1.EOF)) %>

<tr>

</tr>

Repeat1__index=Repeat1__index+1

Repeat1__numRows=Repeat1__numRows-1

Recordset1.MoveNext()

Wend

</table>

<tr>

<% End If ' end MM_offset <> 0 %> </td>

<% End If ' end MM_offset <> 0 %> </td>

<% End If ' end Not MM_atTotal %> </td>

<% 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：）