How To Access Host Objects and Controls Using the ScriptControl

MORE INFORMATION

The objects of the host application can be accessed by the ScriptControl using the AddObject method. AddObject creates a reference to an existing object. The reference name is passed as a parameter to the AddObject method.

Step-by-Step Example

1. Start Visual Basic and invoke a new project. Form1 is created by default.
2. Add two CommandButtons, a List box, a Text box, and a ScriptControl to Form1.
3. Paste the following code in the General Declarations section of Form1:

         Private Sub Command1_Click()
           Dim sObjName As String
           sObjName = InputBox("Enter the the name for the control " _
                      & List1.Text, "AddObject Example", List1.Text)
           ScriptControl1.AddObject sObjName, Form1.Controls(List1.ListIndex)
           MsgBox "Now you can use the keyword """ & sObjName & """" & _
                  vbCrLf &  "to access the properties and methods of " & _
                  List1.Text & vbCrLf & vbCrLf & "Write some statements " & _
                  "in the textbox and click on ""Text Script""", vbInformation
         End Sub
   
         Private Sub Command2_Click()
           ScriptControl1.ExecuteStatement Text1.Text
         End Sub
   
         Private Sub Form_Load()
           Dim C as Control
           For Each c In Form1.Controls
             List1.AddItem c.Name
           Next
           List1.ListIndex = 0
           Command1.Caption = "Add the " & vbCrLf & List1.Text & " object" _
                              & vbCrLf & "for scripting"
           Command2.Caption = "Test script"
           ScriptControl1.AddObject "ctrls", Form1.Controls
           Text1 = "msgbox ""The number of controls is: "" & ctrls.count"
         End Sub
   
         Private Sub List1_Click()
           Command1.Caption = "Add the " & vbCrLf & List1.Text & " object" _
                              & vbCrLf & "for scripting"
         End Sub
   						

4. Run the project. In the Form load, the controls collection is already exported by using AddObject. Click the "Test Script" button to execute the statement in the Text box and to display the number of controls on the form.
5. The List box shows the names of controls present in the form. Click to select "Command1," and click the "Add Command1 object" button. Press OK in the Input box. Type the following text in the Text box and then click "Test Script" to display the caption:
   
   Msgbox Command1.Caption
6. In the List box, click to select "List1. "Click the "Add List1 object," button and, in the Input box, change the name to "MyList." Type the following text in the Text box and click "Text Script" to move the List box:
   
   MyList.Left = 1000

As the remaining steps illustrate, the reference to the objects can be made global to the script. When the reference is global, the methods can be called just by naming the method without using the <Object>.<Method/Property> syntax. The ScriptControl can access objects defined by user-defined classes as well.

1. Using the project you created in the previous steps, add another Command button to Form1.
2. Add the following code to Form1:

         Private Sub Command3_Click()
           Dim MyObj As New Class1, bGlobal
           bGlobal = MsgBox("The object Myobj is added for scripting. " _
                     & vbCrLf & "Do you want its members to be global?", _
                     vbYesNo + vbInformation, "AddObject example")
           If bGlobal = vbYes Then
             ScriptControl1.AddObject "MyObject", MyObj, True
           Else
             ScriptControl1.AddObject "MyObject", MyObj, False
           End If
           MsgBox "Now you can use the keyword ""MyObject"" to access " & _
                  "all its members" ,vbInformation
         End Sub
   						

3. Add a new class module, and paste the following code into the class module:

         Public Sub Test()
           MsgBox "The is Test method in Class1"
         End Sub
   						

4. Run the project. Click the Command3 button. A Message box appears to determine if the reference is to be set as global or not. Select Yes, and, in the Text box, enter the word "Test" without the quotes. Click "Test Script."