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CompareBookmarks method example (VB)

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Applies to: Access 2013, Office 2013

This example demonstrates the CompareBookmarks method. The relative value of bookmarks is seldom needed unless a particular bookmark is somehow special.

Designate a random row of a Recordset derived from the Authors table as the target of a search. Then display the position of each row relative to that target.

 
'BeginCompareBookmarksVB 
 
 'To integrate this code 
 'replace the data source and initial catalog values 
 'in the connection string 
 
Public Sub Main() 
 On Error GoTo ErrorHandler 
 
 ' recordset and connection variables 
 Dim rstAuthors As ADODB.Recordset 
 Dim Cnxn As ADODB.Connection 
 Dim strSQLAuthors As String 
 Dim strCnxn As String 
 
 ' comparison variables 
 Dim count As Integer 
 Dim target As Variant 
 Dim result As Long 
 Dim strAnswer As String 
 Dim strTitle As String 
 strTitle = "CompareBookmarks Example" 
 
 ' Open a connection 
 Set Cnxn = New ADODB.Connection 
 strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _ 
 "Initial Catalog='Pubs';Integrated Security='SSPI';" 
 Cnxn.Open strCnxn 
 
 ' Open recordset as a static cursor type recordset 
 Set rstAuthors = New ADODB.Recordset 
 strSQLAuthors = "SELECT * FROM Authors" 
 rstAuthors.Open strSQLAuthors, Cnxn, adOpenStatic, adLockReadOnly, adCmdText 
 
 count = rstAuthors.RecordCount 
 Debug.Print "Rows in the Recordset = "; count 
 
 ' Exit if an empty recordset 
 If count = 0 Then Exit Sub 
 
 ' Get position between 0 and count -1 
 Randomize 
 count = (Int(count * Rnd)) 
 Debug.Print "Randomly chosen row position = "; count 
 ' Move row to random position 
 rstAuthors.Move count, adBookmarkFirst 
 ' Remember the mystery row 
 target = rstAuthors.Bookmark 
 
 count = 0 
 rstAuthors.MoveFirst 
 ' Loop through recordset 
 Do Until rstAuthors.EOF 
 result = rstAuthors.CompareBookmarks(rstAuthors.Bookmark, target) 
 
 If result = adCompareNotEqual Then 
 Debug.Print "Row "; count; ": Bookmarks are not equal." 
 ElseIf result = adCompareNotComparable Then 
 Debug.Print "Row "; count; ": Bookmarks are not comparable." 
 Else 
 Select Case result 
 Case adCompareLessThan 
 strAnswer = "less than" 
 Case adCompareEqual 
 strAnswer = "equal to" 
 Case adCompareGreaterThan 
 strAnswer = "greater than" 
 Case Else 
 strAnswer = "in error comparing to" 
 End Select 
 'show the results row-by-row 
 Debug.Print "Row position " & count & " is " & strAnswer & " the target." 
 End If 
 
 count = count + 1 
 rstAuthors.MoveNext 
 Loop 
 
 ' clean up 
 rstAuthors.Close 
 Cnxn.Close 
 Set rstAuthors = Nothing 
 Set Cnxn = Nothing 
 Exit Sub 
 
ErrorHandler: 
 ' clean up 
 If Not rstAuthors Is Nothing Then 
 If rstAuthors.State = adStateOpen Then rstAuthors.Close 
 End If 
 Set rstAuthors = Nothing 
 
 If Not Cnxn Is Nothing Then 
 If Cnxn.State = adStateOpen Then Cnxn.Close 
 End If 
 Set Cnxn = Nothing 
 
 If Err <> 0 Then 
 MsgBox Err.Source & "-->" & Err.Description, , "Error" 
 End If 
 
End Sub 
'EndCompareBookmarksVB