Move 方法范例

该范例使用 Move 方法定位基于用户输入的记录指针。

Public Sub MoveX()   Dim rstAuthors As ADODB.Recordset
   Dim strCnn As String
   Dim varBookmark As Variant
   Dim strCommand As String
   Dim lngMove As Long   ' 打开 Authors 表的记录集。
      strCnn = "Provider=sqloledb;" & _
      "Data Source=srv;Initial Catalog=pubs;User Id=sa;Password=; "
   Set rstAuthors = New ADODB.Recordset
   rstAuthors.CursorType = adOpenStatic
   ' 使用客户端游标以允许使用 AbsolutePosition 属性。
   rstAuthors.CursorLocation = adUseClient
   rstAuthors.Open "SELECT au_id, au_fname, au_lname, city, state " & _
      "FROM Authors ORDER BY au_lname", strCnn, , , adCmdText
         rstAuthors.MoveFirst   Do While True
      ' 显示有关当前记录的信息并询问要移动的记录数。      strCommand = InputBox( _
         "Record " & rstAuthors.AbsolutePosition & _
         " of " & rstAuthors.RecordCount & vbCr & _
         "Author: " & rstAuthors!au_fname & _
         " " & rstAuthors!au_lname & vbCr & _
         "Location: " & rstAuthors!City & _
         ", " & rstAuthors!State & vbCr & vbCr & _
         "Enter number of records to Move " & _
         "(positive or negative).")      If strCommand = "" Then Exit Do      ' 保存书签以防 Move 向前或向后移动太远。
      varBookmark = rstAuthors.Bookmark      ' Move 方法需要数据类型为长整型的参数。
      lngMove = CLng(strCommand)
      rstAuthors.Move lngMove      ' 捕获 BOF 或 EOF。
      If rstAuthors.BOF Then
         MsgBox "Too far backward! " & _
            "Returning to current record."
         rstAuthors.Bookmark = varBookmark
      End If
      If rstAuthors.EOF Then
         MsgBox "Too far forward! " & _
            "Returning to current record."
         rstAuthors.Bookmark = varBookmark
      End If
   Loop
   rstAuthors.CloseEnd Sub

VBScript 版本

下面是使用 VBScript 编写、并用于 Active Server Page (ASP) 的相同范例。如需查看该完整功能范例,请使用与 IIS 一同安装并位于 C:\InetPub\ASPSamp\AdvWorks 的数据源 AdvWorks.mdb,来创建名为 AdvWorks 的系统“数据源名称”(DSN)。这是 Microsoft Access 数据库文件。请使用查找命令定位文件 Adovbs.inc,并将其放入计划使用的目录中。请将以下代码剪切并粘贴到记事本或其他文本编辑器中,另存为“Move.asp”。这样,便可在任何客户端浏览器中查看结果。

请输入字母或非整数查看错误处理的运作。

<!-- #Include file="ADOVBS.INC" -->
<% Language = VBScript %>
<HTML><HEAD>
<TITLE>ADO Move Methods</TITLE></HEAD>
<BODY> 
<FONT FACE="MS SANS SERIF" SIZE=2>
<Center>
<H3>ADO Move Methods</H3><%
 ' 创建并打开 Connection 对象。
Set OBJdbConnection = Server.CreateObject("ADODB.Connection") 
OBJdbConnection.Open "AdvWorks" 
' 创建并打开 Recordset 对象。
Set RsCustomerList = Server.CreateObject("ADODB.Recordset")
RsCustomerList.ActiveConnection = OBJdbConnection
RsCustomerList.CursorType = adOpenKeyset
RsCustomerList.LockType = adLockOptimistic
RsCustomerList.Source = "Customers"RsCustomerList.Open ' 检查该会话中用户移动的数目,以窗体中的数量作为增量。
Session("Clicks") = Session("Clicks") + Request.Form("MoveAmount")
Clicks = Session("Clicks")
' 移动到上次已知的记录集位置加上由 Form Post 方法传递的数量。
RsCustomerList.Move CInt(Clicks)' 出错处理。
   If RsCustomerList.EOF Then
         Session("Clicks") = RsCustomerList.RecordCount
         Response.Write "This is the Last Record"
         RsCustomerList.MoveLast
      Else If RsCustomerList.BOF Then
         Session("Clicks") = 1
         RsCustomerList.MoveFirst
         Response.Write "This is the First Record"
      End If
   End If%><H3>Current Record Number is <BR>
<% If Session("Clicks") = 0 Then 
Session("Clicks") = 1
End If
Response.Write(Session("Clicks") )%> of <%=RsCustomerList.RecordCount%></H3>
<HR>
<Center><TABLE COLSPAN=8 CELLPADDING=5 BORDER=0><!-- Customer 表的 BEGIN 列标头行 --><TR><TD ALIGN=CENTER BGCOLOR="#008080">
<FONT STYLE="ARIAL NARROW" COLOR="#ffffff" SIZE=1>Company Name</FONT>
</TD>
<TD ALIGN=CENTER BGCOLOR="#008080">
<FONT STYLE="ARIAL NARROW" COLOR="#ffffff" SIZE=1>Contact Name</FONT>
</TD>
<TD ALIGN=CENTER WIDTH=150 BGCOLOR="#008080">
<FONT STYLE="ARIAL NARROW" COLOR="#ffffff" SIZE=1>Phone Number</FONT>
</TD>
<TD ALIGN=CENTER BGCOLOR="#008080">
<FONT STYLE="ARIAL NARROW" COLOR="#ffffff" SIZE=1>City</FONT>
</TD>
<TD ALIGN=CENTER BGCOLOR="#008080">
<FONT STYLE="ARIAL NARROW" COLOR="#ffffff" SIZE=1>State/Province</FONT>
</TD></TR><!-- 显示 Customer 表的 ADO 数据 -->  <TR>
  <TD BGCOLOR="f7efde" ALIGN=CENTER> 
  <FONT STYLE="ARIAL NARROW" SIZE=1> 
  <%= RSCustomerList("CompanyName")%> 
  </FONT></TD>
  <TD BGCOLOR="f7efde" ALIGN=CENTER>
  <FONT STYLE="ARIAL NARROW" SIZE=1> 
  <%= RScustomerList("ContactLastName") & ", " %> 
  <%= RScustomerList("ContactFirstName") %> 
  </FONT></TD>
  <TD BGCOLOR="f7efde" ALIGN=CENTER>
  <FONT STYLE="ARIAL NARROW" SIZE=1>
   
  <%= RScustomerList("PhoneNumber")%> 
 </FONT></TD>
  <TD BGCOLOR="f7efde" ALIGN=CENTER>
  <FONT STYLE="ARIAL NARROW" SIZE=1> 
  <%= RScustomerList("City")%> 
  </FONT></TD>
  <TD BGCOLOR="f7efde" ALIGN=CENTER>
  <FONT STYLE="ARIAL NARROW" SIZE=1> 
  <%= RScustomerList("StateOrProvince")%> 
  </FONT></TD>
  </TR> </Table></FONT>
<HR>
<Input Type = Button Name = cmdDown  Value = "<  ">
<Input Type = Button Name = cmdUp Value = " >">
<H5>Click Direction Arrows for Previous or Next Record
<BR> Click Move Amount to use Move Method
Enter Number of Records to Move + or - </H5><Table><Form Method = Post Action="Move.asp" Name=Form><TR><TD><Input Type="Button" Name = Move Value="Move Amount "></TD><TD></TD><TD>
<Input Type="Text" Size="4" Name="MoveAmount" Value = 0></TD><TR>
</Form></Table></Center></BODY><Script Language = "VBScript">Sub Move_OnClick
' 确认输入的移动值为整型。
If IsNumeric(Document.Form.MoveAmount.Value)Then
   Document.Form.MoveAmount.Value = CInt(Document.Form.MoveAmount.Value)
   Document.Form.Submit
Else
   MsgBox "You Must Enter a Number", ,"ADO-ASP Example"
   Document.Form.MoveAmount.Value = 0
End IfEnd SubSub cmdDown_OnClickDocument.Form.MoveAmount.Value = -1
Document.Form.SubmitEnd SubSub cmdUp_OnClickDocument.Form.MoveAmount.Value = 1
Document.Form.SubmitEnd Sub</Script>
</HTML>
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