MoveFirst, MoveLast, MoveNext, and MovePrevious Methods Example
This example uses the MoveFirst, MoveLast, MoveNext, and MovePrevious methods to move the record pointer of a Recordset based on the supplied command. The MoveAny procedure is required for this procedure to run.
Public Sub MoveFirstX()
Dim rstAuthors As ADODB.Recordset
Dim strCnn As String
Dim strMessage As String
Dim intCommand As Integer
' Open recordset from Authors table.
strCnn = "driver={SQL Server};server=srv;" & _
"uid=sa;pwd=;database=pubs"
Set rstAuthors = New ADODB.Recordset
rstAuthors.CursorType = adOpenStatic
' Use client cursor to enable AbsolutePosition property.
rstAuthors.CursorLocation = adUseClient
rstAuthors.Open "authors", strCnn, , , adCmdTable
' Show current record information and get user's method choice.
Do While True
strMessage = "Name: " & rstAuthors!au_fName & " " & _
rstAuthors!au_lName & vbCr & "Record " & _
rstAuthors.AbsolutePosition & " of " & _
rstAuthors.RecordCount & vbCr & vbCr & _
"[1 - MoveFirst, 2 - MoveLast, " & vbCr & _
"3 - MoveNext, 4 - MovePrevious]"
intCommand = Val(Left(InputBox(strMessage), 1))
If intCommand < 1 Or intCommand > 4 Then Exit Do
' Call method based on user's input.
MoveAny intCommand, rstAuthors
Loop
rstAuthors.Close
End Sub
Public Sub MoveAny(intChoice As Integer, _
rstTemp As Recordset)
' Use specified method, trapping for BOF and EOF.
Select Case intChoice
Case 1
rstTemp.MoveFirst
Case 2
rstTemp.MoveLast
Case 3
rstTemp.MoveNext
If rstTemp.EOF Then
MsgBox "Already at end of recordset!"
rstTemp.MoveLast
End If
Case 4
rstTemp.MovePrevious
If rstTemp.BOF Then
MsgBox "Already at beginning of recordset!"
rstTemp.MoveFirst
End If
End Select
End Sub
VBScript Version
The following is the same example written in VBScript to be used in an Active Server Page (ASP). To view this example, you need to create a system Data Source Name (DSN) called AdvWorks for the Microsoft Access database file AdvWorks.mdb, which is installed with Microsoft Internet Information Server and located at C:\InetPub\ASPSamp\AdvWorks. Locate the file adovbs.inc and place it in the directory you plan to use. Cut and paste the following code to Notepad or another text editor and save it as MoveOne.asp. You can view the result in any client browser.
Try moving beyond the upper or lower limits of the recordset to see error handling work.
<!-- #Include file="ADOVBS.INC" -->
<% Language = VBScript %>
<HTML><HEAD>
<TITLE>ADO 1.5 MoveNext MovePrevious MoveLast MoveFirst Methods</TITLE></HEAD>
<BODY>
<FONT FACE="MS SANS SERIF" SIZE=2>
<Center>
<H3>ADO Methods<BR>MoveNext MovePrevious MoveLast MoveFirst</H3>
<!-- Create Connection and Recordset Objects on Server -->
<%
'Create and Open Connection Object
Set OBJdbConnection = Server.CreateObject("ADODB.Connection")
OBJdbConnection.Open "AdvWorks"
'Create and Open Recordset Object
Set RsCustomerList = Server.CreateObject("ADODB.Recordset")
RsCustomerList.ActiveConnection = OBJdbConnection
RsCustomerList.CursorType = adOpenKeyset
RsCustomerList.LockType = adLockOptimistic
RsCustomerList.Source = "Customers"
RsCustomerList.Open
' Check Request.Form collection to see if any moves are recorded
If Not IsEmpty(Request.Form("MoveAmount")) Then
'Keep track of the number and direction of moves this session
Session("Moves") = Session("Moves") + Request.Form("MoveAmount")
Clicks = Session("Moves")
'Move to last known position
RsCustomerList.Move CInt(Clicks)
'Check if move is + or - and do error checking
If CInt(Request.Form("MoveAmount")) = 1 Then
If RsCustomerList.EOF Then
Session("Moves") = RsCustomerList.RecordCount
RsCustomerList.MoveLast
End If
RsCustomerList.MoveNext
End If
If Request.Form("MoveAmount") < 1 Then
RsCustomerList.MovePrevious
End If
'Check if First Record or Last Record Command Buttons Clicked
If Request.Form("MoveLast") = 3 Then
RsCustomerList.MoveLast
Session("Moves") = RsCustomerList.RecordCount
End If
If Request.Form("MoveFirst") = 2 Then
RsCustomerList.MoveFirst
Session("Moves") = 1
End If
End If
' Do Error checking for combination of Move Button clicks
If RsCustomerList.EOF Then
Session("Moves") = RsCustomerList.RecordCount
RsCustomerList.MoveLast
Response.Write "This is the Last Record"
End If
If RsCustomerList.BOF Then
Session("Moves") = 1
RsCustomerList.MoveFirst
Response.Write "This is the First Record"
End If
%>
<H3>Current Record Number is <BR>
<!-- Display Current Record Number and Recordset Size -->
<% If IsEmpty(Session("Moves")) Then
Session("Moves") = 1
End If
%>
<%Response.Write(Session("Moves") )%> of <%=RsCustomerList.RecordCount%></H3>
<HR>
<Center><TABLE COLSPAN=8 CELLPADDING=5 BORDER=0>
<!-- BEGIN column header row for Customer Table-->
<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>
<!--Display ADO Data from Customer Table-->
<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 = " >">
<BR>
<Input Type = Button Name = cmdFirst Value = "First Record">
<Input Type = Button Name = cmdLast Value = "Last Record">
<H5>Click Direction Arrows to Use MovePrevious or MoveNext
<BR> </H5>
<!-- Use Hidden Form Fields to send values to Server -->
<Form Method = Post Action="MoveOne.asp" Name=Form>
<Input Type="Hidden" Size="4" Name="MoveAmount" Value = 0>
<Input Type="Hidden" Size="4" Name="MoveLast" Value = 0>
<Input Type="Hidden" Size="4" Name="MoveFirst" Value = 0>
</Form></BODY>
<Script Language = "VBScript">
Sub cmdDown_OnClick
'Set Values in Form Input Boxes and Submit Form
Document.Form.MoveAmount.Value = -1
Document.Form.Submit
End Sub
Sub cmdUp_OnClick
Document.Form.MoveAmount.Value = 1
Document.Form.Submit
End Sub
Sub cmdFirst_OnClick
Document.Form.MoveFirst.Value = 2
Document.Form.Submit
End Sub
Sub cmdLast_OnClick
Document.Form.MoveLast.Value = 3
Document.Form.Submit
End Sub
</Script></HTML>
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