IguanoidWare: IwDBS

The Package:

The package contains (will contain?? need a small time do publish...) some elements:

• IwDB.dll: is the library core... an ActiveX DLL written in Visual Basic.
• ASP: is a directory that contains the files you need to put in a (custom) folder of the web server you are using. If you don't plan to use a remote connection you don't need it. If you need, instead, you have to put the files in a web directory visible from the extern.
• Tutorials: probably I will put in a direcory some tutorials and example projects to explain the usage of the library. You will find some example code on this page too... Take a look to have an idea of how the library works and how to use it.

Some details:

First of all, the few, simple methods of the object supplied by this DLL, set up the more often used (surely by me. I think not just...) options for a use with a M$-Access database (but it could work with other too... I think... if they supports all the features used by this library) and manages a connection-less use of ADO.Recordset objects (as suggested by M$...). But the real power of this library is that it can manage, with the same class interface, a local (or LAN) connection and a REMOTE connection. This means that you can write software in Visual Basic (or other languages that supports this kind of DLLs) that read and write to a database located on a web-server on the NET. It's not all... with the same code, your programs, can use a local or remote database, without the need of changing a line of code... only setting a little property...
This is the ConnectionType property of the IwConnection object that can be set on IwLocal or IwRemote.
Coming soon other details...

Class Interfaces Definitions:

Main class is IwDB.IwConnection.
Here's a list of public class members:

Property ASPPath As String

Sets/Returns the path on the remote host where are located the IwDBS library ASP files (used only in remote connections)

Sub BeginTrans()

Just like ADO.Connection counterpart (nestable)

Sub CommitTrans()

Just like ADO.Connection counterpart

Sub Connect()

Simple... mh? No routine arguments (use class properties)

Property ConnectionType As IwDB.IwConnectionType

Sets/Returns the kind of connection (IwCNLocal, IwCNRemote)

Property DBName As String

Sets/Returns the name of the database file (without path)

Property DBPassword As String

Sets/Returns the database password (is used). Users and groups are not supported yet.

Property DBPath As String

Sets/Returns the path where is located the database file (used in both local and remote connections)

Sub Disconnect()

Self explaining... ;)

Property DoEventsWhileLoading As Boolean

Setting this to true causes the form's events to be executed while a http request is sent to remote host (DoEvents is called repeatedly while waiting for HTTP response. Used only in remote connections)

Sub Execute(sSQL As String)

Similar to ADO.Connection counterpart but only the command argument is used. Note that it is a Sub so it return no recordset objects.. to do this, use the GetRs function instead (they was implemented as two separate methods for speed reasons in the case of a remote connection).

Function GetRs(sSQL As String) As ADODB.Recordset

Similar to ADO.Connection.Execute function. Note that there is only the command argument and that you have to use the Execute() routine where you don't need a recordset to be returned (Ex. a SQL DELETE query) for speed reasons.

Property HostName As String

Set/Returns the name of the remote host where database and IwDBS library ASP files are located (Do not specify ant protocol or path. Ex "www.myhost.com")

Sub RollbackTrans()

Just like ADO.Connection counterpart

Function SaveRs(Rs As ADODB.Recordset) As ADODB.Recordset

This is an important class member.
When you get a recordset object through the GetRs() function, it returns it in connection-less mode, so changes are not written to disk until you call this function. When using a remote connection set the recordset object that you are saving to the one that is returned by the function to get autonumber values generated by database driver or similar data. See code examples.

Property Settings As IwDB.IwInternalCNData

The only aim of this property is to quikly create a clone connection to anothes one without the need of copying all properties manually. To do this you have to set only the ConnectionType Property and THEN the Settings property, so you can call Connect() method.

Property ShowWaitMessage As Boolean

NOT COMPLETED YET!!!
Setting this property to true causes a built-in wait dialog box to appear while doing HTTP requests.

Installation tips:

Not available yet... I'm sorry for the inconvenience... coming soon!

Some example code:

I put some example code... without too much comments... for now. This code speaks by itself...
This is the code needed for a local connection/disconnection and a read/write from DB. Just simple, uhm?


Private Sub CmdLocalConnect_Click()
    'Connection to a local DB using
    'global instance of IwDB.IwConnection class
    ConnectionType = IwLocal
    DBName = "MyDB.MDB"
    DBPath = App.Path & "\"
    Connect
End Sub


Private Sub CmdAddRecord_Click()
    'Get an empty recordset
    'and add record(s)
    'using global member functions
    'GetRs() and SaveRs()
    Dim Rs As ADODB.Recordset
    Dim MyID As Long
    
    Set Rs = GetRs("SELECT * FROM MyTable WHERE ID=" & -1)
    'Now Rs is "connectionless"...
    'so Rs.ActiveConnection is now Nothing
    'and changes are not made on disk
    Rs.AddNew 'add a record
    Rs("Username") = "MrBrown"
    Set Rs = SaveRs(Rs) 'Now saving the rs
    '"Set Rs = SaveRs(Rs)" is needed only
    'for remote CNs. In local mode
    'a "SaveRs Rs" should work
    'but this longer syntax works always.
    MyID = Rs("ID") 'reading an autonumber value
    Set Rs = Nothing
End Sub

Private Sub CmdDisconnect_Click()
    Disconnect
End Sub


Other code is arriving soon...