求高手帮忙解决方案

2012-02-13

求高手帮忙opendatabase()怎么使用？求高手帮，最好带有实例[解决办法]建议参考一下帮助手册吧。引用OpenData

求高手帮忙
opendatabase()怎么使用？求高手帮，最好带有实例

[解决办法]
建议参考一下帮助手册吧。

引用OpenDatabase Method

Opens a specified database in a Workspace object and returns a reference to the Database object that represents it.

Syntax

Set database = workspace.OpenDatabase (dbname, options, read-only, connect)

The OpenDatabase method syntax has these parts.

Part Description
database An object variable that represents the Database object that you want to open.
workspace Optional. An object variable that represents the existing Workspace object that will contain the database. If you don't include a value for workspace, OpenDatabase uses the default workspace.
dbname A String that is the name of an existing Microsoft Jet database file, or the data source name (DSN) of an ODBC data source. See the Name property for more information about setting this value.
options Optional. A Variant that sets various options for the database, as specified in Settings.
read-only Optional. A Variant (Boolean subtype) value that is True if you want to open the database with read-only access, or False (default) if you want to open the database with read/write access.
connect Optional. A Variant (String subtype) that specifies various connection information, including passwords.

Settings

For Microsoft Jet workspaces, you can use the following values for the options argument.

Setting Description
True Opens the database in exclusive mode.
False (Default) Opens the database in shared mode.

For ODBCDirect workspaces, the options argument determines if and when to prompt the user to establish the connection. You can use one of the following constants.

Constant Description
dbDriverNoPrompt The ODBC Driver Manager uses the connection string provided in dbname and connect. If you don't provide sufficient information, a run-time error occurs.
dbDriverPrompt The ODBC Driver Manager displays the ODBC Data Sources dialog box, which displays any relevant information supplied in dbname or connect. The connection string is made up of the DSN that the user selects via the dialog boxes, or, if the user doesn't specify a DSN, the default DSN is used.
dbDriverComplete (Default) If the connect and dbname arguments include all the necessary information to complete a connection, the ODBC Driver Manager uses the string in connect. Otherwise it behaves as it does when you specify dbDriverPrompt.
dbDriverCompleteRequired This option behaves like dbDriverComplete except the ODBC driver disables the prompts for any information not required to complete the connection.

Remarks

When you open a database, it is automatically added to the Databases collection. Further, in an ODBCDirect workspace, the Connection object corresponding to the new Database object is also created and appended to the Connections collection of the same Workspace object.

Some considerations apply when you use dbname:

If it refers to a database that is already open for exclusive access by another user, an error occurs.

If it doesn't refer to an existing database or valid ODBC data source name, an error occurs.

If it's a zero-length string ("") and connect is "ODBC;", a dialog box listing all registered ODBC data source names is displayed so the user can select a database.

If you're opening a database through an ODBCDirect workspace and you provide the DSN in connect, you can set dbname to a string of your choice that you can use to reference this database in subsequent code.
The connect argument is expressed in two parts: the database type, followed by a semicolon (;) and the optional arguments. You must first provide the database type, such as "ODBC;" or "FoxPro 2.5;". The optional arguments follow in no particular order, separated by semicolons. One of the parameters may be the password (if one is assigned). For example:

"FoxPro 2.5; pwd=mypassword"

Using the NewPassword method on a Database object other than an ODBCDirect database changes the password parameter that appears in the ";pwd=..." part of this argument. You must supply the options and read-only arguments to supply a source string. See the Connect property for syntax.

To close a database, and thus remove the Database object from the Databases collection, use the Close method on the object.

Note When you access a Microsoft Jet-connected ODBC data source, you can improve your application's performance by opening a Database object connected to the ODBC data source, rather than by linking individual TableDef objects to specific tables in the ODBC data source.

[解决办法]

引用OpenDatabase Method Example

This example uses the OpenDatabase method to open one Microsoft Jet database and two Microsoft Jet-connected ODBC databases.

Sub OpenDatabaseX()

Dim wrkJet As Workspace
Dim dbsNorthwind As Database
Dim dbsPubs As Database
Dim dbsPubs2 As Database
Dim dbsLoop As Database
Dim prpLoop As Property

' Create Microsoft Jet Workspace object.
Set wrkJet = CreateWorkspace("", "admin", "", dbUseJet)

' Open Database object from saved Microsoft Jet database
' for exclusive use.
MsgBox "Opening Northwind..."
Set dbsNorthwind = wrkJet.OpenDatabase("Northwind.mdb", _
True)

' Open read-only Database object based on information in
' the connect string.
MsgBox "Opening pubs..."

' Note: The DSN referenced below must be set to
' use Microsoft Windows NT Authentication Mode to
' authorize user access to the Microsoft SQL Server.
Set dbsPubs = wrkJet.OpenDatabase("Publishers", _
dbDriverNoPrompt, True, _
"ODBC;DATABASE=pubs;DSN=Publishers")

' Open read-only Database object by entering only the
' missing information in the ODBC Driver Manager dialog
' box.
MsgBox "Opening second copy of pubs..."
Set dbsPubs2 = wrkJet.OpenDatabase("Publishers", _
dbDriverCompleteRequired, True, _
"ODBC;DATABASE=pubs;DSN=Publishers;")

' Enumerate the Databases collection.
For Each dbsLoop In wrkJet.Databases
Debug.Print "Database properties for " & _
dbsLoop.Name & ":"

On Error Resume Next
' Enumerate the Properties collection of each Database
' object.
For Each prpLoop In dbsLoop.Properties
If prpLoop.Name = "Connection" Then
' Property actually returns a Connection object.
Debug.Print " Connection[.Name] = " & _
dbsLoop.Connection.Name
Else
Debug.Print " " & prpLoop.Name & " = " & _
prpLoop
End If
Next prpLoop
On Error GoTo 0

Next dbsLoop

dbsNorthwind.Close
dbsPubs.Close
dbsPubs2.Close
wrkJet.Close

End Sub

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求高手帮忙解决方案