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The information in this article applies to:
- Microsoft Visual Basic programming system for Windows, version 3.0
SUMMARY
The example in this article demonstrates how to build a Microsoft Access
database without having a database or database template already built. The
example uses a Btrieve for Windows database file to supply the data to be
placed into the newly created Microsoft Access database.
MORE INFORMATION
NOTE: You will need to have a Btrieve for Windows database file
already built to test this example. The Btrieve for Windows
database file tested with this example can be sent upon request.
Steps to demonstrate the example
- Start Visual Basic or from the File menu, choose New Project (ALT, F, N)
if Visual Basic is already running. Form1 is created by default.
- Add three command buttons and two grid controls using GRID.VBX to Form1.
Using the following table as a guide, set the properties of the controls
you added in step 2.
Control Property New Value
----------------------------------------------------------------------
Command1 Caption "Press to Load Btrieve File and Display in Grid"
Command2 Caption "Press to Transfer Data and Build New DB"
Command3 Caption "Press to Display Data from the New Database"
Grid1 Cols 4
Grid1 Rows 15
Grid2 Cols 4
Grid2 Rows 15
- Review the following brief outline of the table from the Btrieve for
Windows database:
Table Name: Big_Tab
Field Names Field Type Field Size
-----------------------------------------
PrimaryKey Long Integer
MyMoney Currency
MyString Text 154
Index Names Index Fields Unique Primary
---------------------------------------------------
tabindex +PrimaryKey Yes No
- Add the following variables and constants to the (general) section of
Form1:
Dim PrimaryKeys(30) As Long
Dim Money(30) As Currency
Dim Strings(30) As String * 154
Const DB_LONG = 4
Const DB_TEXT = 10
Const DB_CURRENCY = 5
Const DB_LANG_GENERAL = ";LANGID=0x0809;CP=1252;COUNTRY=0"
- Add the following code to the Form Load event procedure:
Sub Form_Load ()
Show
grid1.ColWidth(1) = 1000 'For PK ID
grid1.ColWidth(2) = 2000 'For Money
grid1.ColWidth(3) = 5000 'For Story
grid1.Col = 1
grid1.Row = 0
grid1.Text = "Primary Keys" 'Header for PK ID
grid1.Col = 2
grid1.Row = 0
grid1.Text = "Money" 'Header for Money
grid1.Col = 3
grid1.Row = 0
grid1.Text = "Big String" 'Header for Story
grid2.ColWidth(1) = 1000 'For PK ID
grid2.ColWidth(2) = 2000 'For Money
grid2.ColWidth(3) = 5000 'For Story
grid2.Col = 1
grid2.Row = 0
grid2.Text = "Prime's" 'Header for PK ID
grid2.Col = 2
grid2.Row = 0
grid2.Text = "Your Money" 'Header for Money
grid2.Col = 3
grid2.Row = 0
grid2.Text = "Your Story" 'Header for Story
End Sub
- Add the following code to the Command1 Click event procedure:
Sub Command1_Click ()
Dim db As Database
Dim conn$
Dim dt As Table
conn$ = "Btrieve;"
' Enter the following Set as one, single line:
Set db = OpenDatabase("C:\articles\btrvwin\file.ddf", False, False,
conn$)
Set dt = db.OpenTable("Big_Tab")
' Counter for loading the grid
For i% = 1 To 10 'Grab the first ten for a test
grid1.Col = 1
grid1.Row = i%
grid1.Text = dt(0) 'Load the grid
PrimaryKeys(i%) = dt(0) 'Load the temporary array
grid1.Col = 2
grid1.Row = i%
grid1.Text = dt(1) 'Load the grid
Money(i%) = dt(1) 'Load the temporary array
grid1.Col = 3
grid1.Row = i%
grid1.Text = dt(2) 'Load the grid
Strings(i%) = dt(2) 'Load the temporary array
dt.MoveNext
Next i%
End Sub
- Add the following code to the Command2 Click event procedure:
Sub Command2_Click ()
Dim newdb As Database
Dim newtb As Table
Dim newtd As New tabledef
Dim newidx As New Index
Dim field1 As New field 'For PK IDs
Dim field2 As New field 'For Money
Dim field3 As New field 'For Story's
screen.MousePointer = 11 'To display the time to build
Set newdb = CreateDatabase("NEWBTWDB.MDB", DB_LANG_GENERAL)
newtd.Name = "Money_Table" '* New table name
field1.Name = "PK_ID" '* Holds PK ID
field1.Type = DB_LONG
newtd.Fields.Append field1
field2.Name = "Money" '* Holds Money
field2.Type = DB_CURRENCY
newtd.Fields.Append field2
field3.Name = "Story" '* Holds Story
field3.Type = DB_TEXT
field3.Size = 154
newtd.Fields.Append field3
newidx.Name = "PK_ID_IDX" '* You have to have an index
newidx.Fields = "PK_ID"
newidx.Primary = True
newtd.Indexes.Append newidx
newdb.TableDefs.Append newtd
Set newtb = newdb.OpenTable("Money_Table")
For i% = 1 To 10
newtb.AddNew
newtb("PK_ID") = PrimaryKeys(i%) 'place in field1
newtb("Money") = Money(i%) 'place in field3
newtb("Story") = Trim$(Strings(i%)) 'place in field4
newtb.Update 'Saving to table
Next i%
newtb.Close '* Close DB's table
newdb.Close '* Close DB
screen.MousePointer = 0 'Set back to show done
End Sub
- Add the following code to the Command3 Click event procedure:
Sub Command3_Click ()
Dim db As Database
Dim t As Table
Dim counter%
Set db = OpenDatabase("NEWBTWDB.MDB")
Set t = db.OpenTable("Money_Table")
counter% = 1 'Start counter at Row=1
Do Until t.EOF
grid2.Col = 1
grid2.Row = counter%
grid2.Text = t(0) 'Load the PK ID
grid2.Col = 2
grid2.Row = counter%
grid2.Text = t(1) 'Load the Money
grid2.Col = 3
grid2.Row = counter%
grid2.Text = t(2) 'Load the Story
counter% = counter% + 1
t.MoveNext
Loop
t.Close
db.Close
End Sub
- From the Run menu, choose Start (ALT, R, S), or press the F5 key to run
the program. First, click the Command1 button. Next, click the Command2
button. Then click the Command3 button. Compare the results.
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