AddObject Method

In This Topic

Description

Exports a native COM Object to JavaScript.

Syntax

Visual Basic
Public Sub AddObject( _ ByVal Name As String, _ ByVal Object As Object, _ Optional ByVal AddMembers As Boolean = False _ )

Visual Basic

Public Sub AddObject( _
   ByVal Name As String, _
   ByVal Object As Object, _
   Optional ByVal AddMembers As Boolean = False _
)

Parameters

Name: Required. The programmatic identifier of the object instance. The object is exposed to JavaScript through this global identifier, also accessible as named property of the window object.
Object: Required. An IDispatch interface pointer of the COM object instance you wish to expose to JavaScript.
AddMembers: Reserved.

Remarks

This technology allows you to use headless COM objects (non-controls) from JavaScript.

Any simple in-process or out-of-process apartment threaded COM object with scalar properties and/or methods with scalar arguments and scalar return value can be wrapped into an V8 object and exposed through a global identifier to the V8 JavaScript context. The method will not work for COM objects that have non-scalar properties or method arguments or method return values.

Visual Basic 6.0 developers, please note that if you wish to expose a local VB6 Class to JavaScript, you must compile your executable as ActiveX EXE. Standard executables will only work while in Visual Basic 6.0 IDE but not if you compile them.

JavaScriptX in-process ActiveX wraps the IDispatch interface pointer you provide, inside an in-process Proxy object and generates a Stub V8 object, which is exported to the Global object of the V8 context. Thus, in JavaScript you can call your COM object directly from any scope. The communication between the Proxy and Stub counterparts is synchronous.

OLE/COM Variants to V8 Values Conversion

JavaScriptX has a powerful OLE/COM Variant to Google V8 Value bi-directional converter that works both for Scalar and Array values, including nested array values (arrays of arrays of variants). JavaScriptX can serialize variant scalars VT_BSTR, VT_UINT, VT_INT, VT_NULL, VT_BOOL, VT_R4, VT_R8, VT_CY, VT_DATE as well as variant safearray of variants VT_ARRAY|VT_VARIANT and even typed arrays VT_ARRAY|VT_BSTR, VT_ARRAY|VT_UINT, VT_ARRAY|VT_INT, VT_ARRAY|VT_BOOL, VT_ARRAY|VT_R4, VT_ARRAY|VT_R8, VT_ARRAY|VT_CY, VT_ARRAY|VT_DATE to Google V8 value objects. Currently serialization of VT_DISPATCH is not supported and therefore you cannot pass OLE/COM Objects to JavaScript with IDispatch members or arguments.

Example

Example (Visual Basic)
Sample Class (Visual Basic)

Private Sub Form_Load()
    
    Set SC = New ScriptControl
    SC.Language = "JavaScript"
    SC.AllowUI = True
    SC.SitehWnd = Me.hWnd
    SC.UseSafeSubset = False
    SC.Timeout = 60
    
    Dim Result As Variant
    
    SC.AddObject "MyClass", MyClass
    Result = SC.Eval("MyClass.C")
        
End Sub

Option Explicit

Public C As Long

Private m_D As Long
Private m_I(100) As Long

Public Property Get D() As Long
    D = m_D
End Property

Public Property Let D(ByRef v As Long)
    m_D = v
End Property

Public Function foo(ByVal a As Long, ByRef b As Long) As Long
    foo = a + b + C + D
End Function