(11 of 18)3/28/ :54:24 AMġ2 Click on the OK button, and you'll be back here (12 of 18)3/28/ :54:24 AMġ3 Notice how the Connection String has been built for you. A few seconds later, this window should appear After clicking on this Message Box, you'll be back at this window. It's a good idea to click on the Test Connection button to ensure that the parameters are correct, and that the Database can be opened. At this point, we've established the parameters for the Connection. For now, let's find and select the BIBLIO.Mdb database using this window (9 of 18)3/28/ :54:24 AMġ0 then click on the Open button (10 of 18)3/28/ :54:24 AMġ1 As you can see, the name of the Database now appears on the Connection Tab. If we had selected an Oracle or SQL Server Provider, this window would look somewhat different, but the idea is the same. For Access Databases, the User Name is 'Admin' by default, and there is no password. After clicking on the Next button, this window appear (8 of 18)3/28/ :54:24 AMĩ We'll need to specify a database name in this window, and we're going to select a sample database that Microsoft ships with both Access and Visual Basic called BIBLIO.MDB (it contains data about books, authors, publishers and titles). If we were connecting to an Oracle or a SQL Server database, we would select that type of Provider here. All we need to do is click on the Custom Property of the Data Control (5 of 18)3/28/ :54:24 AMĦ and a Wizard to build the ConnectionString and the RecordSource Properties will appear (6 of 18)3/28/ :54:24 AMħ Click on the Build Button next to 'Use Connection String', and this window will appear (7 of 18)3/28/ :54:24 AMĨ The names in this window may appear to be gibberish-but in order to connect to a Microsoft Access Database, we'll select Microsoft Jet 4.0 OLE DB Provider as our provider, and then click on the Next button. Coming up with values for these off the top of our head is too much trouble-visual Basic will do it for us. We need to provide values for the CommandType, the ConnectionString, and the RecordSource Properties of the Data Control. In fact, that's our next step-we need to bind the DataGrid to the Data Control, and we do that by bringing up the Properties Window for the DataGrid, and specifying its DataSource Property as Adodc1-the name of our Data Control We still don't have a Connection or a Recordset built-but it won't be long.
Eventually (in just a few minutes), the Data Control will instantiate a Connection and Recordset, and the records from the Recordset will be 'bound' to the Data Grid. Find the ADO DataGrid by selecting Project-Components and looking for Microsoft DataGrid Control (2 of 18)3/28/ :54:24 AMģ If we click on the OK button, the DataGrid will now be added to the Visual Basic Toolbox also (3 of 18)3/28/ :54:24 AMĤ Now let's add both the Data Control and the DataGrid to our form At this point, all we have is an empty DataGrid, and an uninitialized Data (4 of 18)3/28/ :54:24 AMĥ Control. By default, the DAO Data Control is contained in the Visual Basic Toolbox, so you'll need to select Project- Components from the Visual Basic Menu Bar, and select the Microsoft ActiveX Data Control If you click on the OK button, the ActiveX Data Control will then appear in the (1 of 18)3/28/ :54:24 AMĢ Visual Basic Toolbox At this point, we may as well find the ADO DataGrid as well-we'll be needing it in just a few minutes to display the data retrieved from the Recordset (a virtual database table) that we'll be generating. Use the ADO Data Control to create a Connection The first step in using the ADO Data Control to create a Connection to a database is to find the ADO Data Control. In this article, I'd like to show you how you can connect to a Microsoft Database using the ADO Data Control and the ADO Data Grid. 1 Use the ADO Control in your Visual Basic 6 projects Aside from my Database book, I haven't done much writing concerning connection to a Database-and virtually nothing on ADO.
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