ITP 150 – Visual Basic Programming

Internet Controls & VB Script Database Project

This project contains two parts. The first part involves writing a Visual Basic application that references ‘Microsoft Internet Controls.’ The Microsoft Internet Controls library exposes the functionality of the Internet Explorer Browser. The VB Application will launch an instance of Internet Explorer and allow various components to be configured through the VB interface.

The second part of the project involves writing a web page that connects to a database using VBScript. The database being used in this project will be the ‘Nwind.mdb’, the same database used in the previous database projects. In addition to the web page, you will be required to setup a System DSN (from the Control Panels) which establishes the connection to a data source (Nwind.mdb). The VBScript web page will contain various fields of the Products table and allow the user to navigate through the various records.

Part A – Internet Controls

Launch Visual Basic and create a Standard Exe project. The interface of the application should resemble the following:

Before you start coding the application, set a reference to: Microsoft Internet Controls. This library exposes the functionality of the Microsoft Internet Explorer Browser.

Declare a form-level variable as the data type: InternetExplorer

Dim WithEvents ie As InternetExplorer

The click_event of the ‘Start Internet Explorer’ command button should resemble the following code:

Set ie = New InternetExplorer

' set all the UI to invisible

ie.ToolBar = False

ie.StatusBar = False

' set starting size and location

ie.Width = 440

ie.Height = 400

ie.Top = 105

ie.Left = 270

' make ie visible

ie.Visible = True

Code the option buttons to resemble the following code:

Private Sub optNotVisible_Click()

If optNotVisible.Value = True Then

' code to make UI NOT Visible

ie.ToolBar = False

ie.StatusBar = False

End If

End Sub

Private Sub optVisible_Click()

If optVisible.Value = True Then

' code to make UI Visible

ie.ToolBar = True

ie.StatusBar = True

End If

End Sub

Code the ‘Open URL’ command button to resemble the following code:

ie.Navigate txtURL.Text

Code the ‘Refresh’ button as so:

ie.Refresh

Code the ‘Stop’ button as followed:

ie.Stop

Code the ‘Close Internet Explorer’ button as followed:

ie.Quit

Set ie = Nothing

Code the ‘Exit’ button as followed:

Unload Me

Code the form_Unload event to resemble the following code:

On Error Resume Next

' if it's closed, ignore the error...

ie.Quit

' clean up ie object variable

Set ie = Nothing

Finish the application by coding the following four events of the ie object (assuming you are declaring ‘ie’ as InternetExplorer):

Private Sub ie_BeforeNavigate2(ByVal pDisp As Object, URL As Variant, _ Flags As Variant, TargetFrameName As Variant, PostData As Variant, _ Headers As Variant, Cancel As Boolean)

lblStatus.Caption = "Navigation begun..."

End Sub

Private Sub ie_NavigateComplete2(ByVal pDisp As Object, URL As Variant)

lblStatus.Caption = "Navigation complete..."

End Sub

Private Sub ie_DownloadBegin()

lblStatus.Caption = "Download begun..."

End Sub

Private Sub ie_DownloadComplete()

lblStatus.Caption = "Download complete..."

End Sub

Save this part of your project as ‘PartA’ in a folder titled ‘Lastname_Firstname’.

Part B – VBScript Database Project

In order for this VBScript web page to work, a ‘System DSN’ file has to be created. To create the ‘System DSN’, go to the control panels and locate the ‘ODBC Data Sources’ Applet (you will need the appropriate Security Privileges to add a System DSN so make sure you logon as ITP150). After you select the ODBC Data Sources applet, make sure you choose the ‘System DSN’ tab. From the System DSN tab, click on Add. From the next window, Select Microsoft Access Driver. For the DataSource Name, type in ITP150. From the database frame, click on the Select button and search for the Nwind.mdb database. Click the OK button and you are finished setting up the System DSN.

Review the code below. This code should be entered into ‘Notepad’ (located in the Accessories folder from the Start menu), or you may use any other text editor. After reviewing the code, make sure you identify the recordset variables and ADO methods used to navigate through the recordset. You should find similarities between the VBScript code and the ADO code from the database projects. Here is the code that should appear in Notepad:

<hmtl>

<head><title>Anthony's VBScript-Database Project Using ADO</title><head>

<h1>VBScript/ActiveX Data Objects (ADO)</h1>

<br>

<br>

The following fields have been generated automatically based on the schema

information found in the recordset. If the data fields do not appear below this

message you may have to reduce the level of security in your browser.

'*******************************************************************

' Open the recordset / execute the sql query

connect = "data source=itp150;user id=admin;password=;"

query = "select * from products"

adOpenKeyset = 1

rs.Open query, connect, adOpenKeyset

set flds = rs.Fields

'*******************************************************************

' Build the html for viewing the data

' determine width for field-name column

namewid = 0

for i = 0 to flds.Count - 1

' look for length of each field, compare the length to namewid

if len(flds(i).Name) > namewid then namewid = len(flds(i).Name)

' write out html for form-fields

for i = 0 to flds.Count - 1

document.write "<pre>"

s = flds(i).Name

s = s + space( namewid - len(s) + 2 )

s = s + "<input type=text name=fld_" + cstr(i) + ">"

document.write s

document.write "</pre>"

'*******************************************************************

' Build the vbscript for copying data to the form

document.writeln "<script language=""vbscript"">"

document.writeln "sub FillForm"

for i = 0 to flds.Count - 1

s = "fld_" + cstr(i) + ".value = " + "rs.fields(" + cstr(i) + ").value"

document.writeln s

document.writeln "end sub"

' force 'FillForm' to execute immediately

document.writeln "FillForm"

document.writeln "<" + "/" + "script" + ">"

</script>

Sub btnNext_OnClick

if not rs.EOF then

rs.MoveNext

if rs.EOF then

rs.MoveLast

else

FillForm

end if

End Sub

Sub btnPrev_OnClick

if not rs.BOF then

rs.MovePrevious

if rs.BOF then

rs.MoveFirst

else

FillForm

end if

End Sub

Sub btnFirst_OnClick

rs.MoveFirst

FillForm

End Sub

Sub btnLast_OnClick

rs.MoveLast

FillForm

End Sub

</script>

</body>

</html>

The code listed above should produce the following web page:

Save the text fil