Article ID : 182598
Last Review : September 1, 2005
Revision : 3.1
This article was previously published under Q182598

SUMMARY

This article describes how to implement the IObjectSafety interface in Visual Basic controls to mark the controls safe for scripting and initialization. By default, Visual Basic controls use component category entries in the registry to mark the control safe for scripting and initialization. Implementing the IObjectSafety interface is the preferred method. This article contains all the code that is required to implement this interface in Visual Basic controls.

Please keep in mind that a control should only be marked as safe if it is, in fact, safe. This article does not describe the details of marking controls as safe for scripting and initialization; it simply demonstrates how to do it in code. Please refer to the Internet Client Software Development Kit (SDK) documentation for a detailed description of this. See "Safe Initialization and Scripting for ActiveX Controls" under the Component Development section.

MORE INFORMATION

WARNING: One or more of the following functions are discussed in this article: VarPtr, VarPtrArray, VarPtrStringArray, StrPtr, and ObjPtr. These functions are not supported by Microsoft Technical Support. They are not documented in the Visual Basic documentation and are provided in this Knowledge Base article "as is." Microsoft does not guarantee that they will be available in future releases of Visual Basic. For additional information about these functions, click the article number below to view the article in the Microsoft Knowledge Base:

199824 (http://support.microsoft.com/kb/199824/EN-US/) How To Get the Address of Variables in Visual Basic

The following steps illustrate how to create a simple Visual Basic control and mark it safe for scripting and initialization.

1. Create a new folder where you can save all files that you create in this example.
2. Get the OLE Automation Type Library Generator from the Visual Basic CD-ROM. To do this, copy all four files from the CommonToolsVBUnsupprtTyplib folder to your project folder.
3. Copy the following text into Notepad, and save the file in the project folder as Objsafe.odl:

      [
uuid(C67830E0-D11D-11cf-BD80-00AA00575603),
helpstring("VB IObjectSafety Interface"),
version(1.0)
]
library IObjectSafetyTLB
{
importlib("stdole2.tlb");
[
uuid(CB5BDC81-93C1-11cf-8F20-00805F2CD064),
helpstring("IObjectSafety Interface"),
odl
]
interface IObjectSafety:IUnknown {
[helpstring("GetInterfaceSafetyOptions")]
HRESULT GetInterfaceSafetyOptions(
[in] long riid,
[in] long *pdwSupportedOptions,
[in] long *pdwEnabledOptions);

[helpstring("SetInterfaceSafetyOptions")]
HRESULT SetInterfaceSafetyOptions(
[in] long riid,
[in] long dwOptionsSetMask,
[in] long dwEnabledOptions);
}
}
4. At a command prompt, use the CD <path> command to move to the project folder, and type the following command to generate a .tlb file:

MKTYPLIB objsafe.odl /tlb objsafe.tlb
5. From Visual Basic, create an ActiveX Control project. In the Properties list, change the name of the project to IObjSafety and the name of the control to DemoCtl. Put a CommandButton named cmdTest on the control. In the Click event handler of the cmdTest, put a MsgBox "Test" statement.
6. On the Project menu, click References, browse to and add Objsafe.tlb, which you created earlier.
7. Add a new module to your project with the following code, and name the module basSafeCtl:

      Option Explicit

Public Const IID_IDispatch = "{00020400-0000-0000-C000-000000000046}"
Public Const IID_IPersistStorage = _
"{0000010A-0000-0000-C000-000000000046}"
Public Const IID_IPersistStream = _
"{00000109-0000-0000-C000-000000000046}"
Public Const IID_IPersistPropertyBag = _
"{37D84F60-42CB-11CE-8135-00AA004BB851}"

Public Const INTERFACESAFE_FOR_UNTRUSTED_CALLER = &H1
Public Const INTERFACESAFE_FOR_UNTRUSTED_DATA = &H2
Public Const E_NOINTERFACE = &H80004002
Public Const E_FAIL = &H80004005
Public Const MAX_GUIDLEN = 40

Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" _
(pDest As Any, pSource As Any, ByVal ByteLen As Long)
Public Declare Function StringFromGUID2 Lib "ole32.dll" (rguid As _
Any, ByVal lpstrClsId As Long, ByVal cbMax As Integer) As Long

Public Type udtGUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(7) As Byte
End Type

Public m_fSafeForScripting As Boolean
Public m_fSafeForInitializing As Boolean

Sub Main()
m_fSafeForScripting = True
m_fSafeForInitializing = True
End Sub
8. From Project Properties, change the Startup Object to Sub Main to execute the Sub Main above. Use the m_fSafeForScripting and m_fSafeForInitializing variables to specify the values of safe for the scripting and/or initialization variables.
9. Open the code window of your control. Add the following line of code to the Declaration section (right after Option Explicit or as the first):

Implements IObjectSafety
10. Copy the following two procedures to your controls code:

      Private Sub IObjectSafety_GetInterfaceSafetyOptions(ByVal riid As _
Long, pdwSupportedOptions As Long, pdwEnabledOptions As Long)

Dim Rc As Long
Dim rClsId As udtGUID
Dim IID As String
Dim bIID() As Byte

pdwSupportedOptions = INTERFACESAFE_FOR_UNTRUSTED_CALLER Or _
INTERFACESAFE_FOR_UNTRUSTED_DATA

If (riid <> 0) Then
CopyMemory rClsId, ByVal riid, Len(rClsId)

bIID = String$(MAX_GUIDLEN, 0)
Rc = StringFromGUID2(rClsId, VarPtr(bIID(0)), MAX_GUIDLEN)
Rc = InStr(1, bIID, vbNullChar) - 1
IID = Left$(UCase(bIID), Rc)

Select Case IID
Case IID_IDispatch
pdwEnabledOptions = IIf(m_fSafeForScripting, _
INTERFACESAFE_FOR_UNTRUSTED_CALLER, 0)
Exit Sub
Case IID_IPersistStorage, IID_IPersistStream, _
IID_IPersistPropertyBag
pdwEnabledOptions = IIf(m_fSafeForInitializing, _
INTERFACESAFE_FOR_UNTRUSTED_DATA, 0)
Exit Sub
Case Else
Err.Raise E_NOINTERFACE
Exit Sub
End Select
End If
End Sub

Private Sub IObjectSafety_SetInterfaceSafetyOptions(ByVal riid As _
Long, ByVal dwOptionsSetMask As Long, ByVal dwEnabledOptions As Long)
Dim Rc As Long
Dim rClsId As udtGUID
Dim IID As String
Dim bIID() As Byte

If (riid <> 0) Then
CopyMemory rClsId, ByVal riid, Len(rClsId)

bIID = String$(MAX_GUIDLEN, 0)
Rc = StringFromGUID2(rClsId, VarPtr(bIID(0)), MAX_GUIDLEN)
Rc = InStr(1, bIID, vbNullChar) - 1
IID = Left$(UCase(bIID), Rc)

Select Case IID
Case IID_IDispatch
If ((dwEnabledOptions And dwOptionsSetMask) <> _
INTERFACESAFE_FOR_UNTRUSTED_CALLER) Then
Err.Raise E_FAIL
Exit Sub
Else
If Not m_fSafeForScripting Then
Err.Raise E_FAIL
End If
Exit Sub
End If

Case IID_IPersistStorage, IID_IPersistStream, _
IID_IPersistPropertyBag
If ((dwEnabledOptions And dwOptionsSetMask) <> _
INTERFACESAFE_FOR_UNTRUSTED_DATA) Then
Err.Raise E_FAIL
Exit Sub
Else
If Not m_fSafeForInitializing Then
Err.Raise E_FAIL
End If
Exit Sub
End If

Case Else
Err.Raise E_NOINTERFACE
Exit Sub
End Select
End If
End Sub
11. On the File menu, save your project and files. Make an OCX file from your project. Your control now implements the IObjectSafety interface. To test it, insert the control in an .htm file.
http://bbs.nsfocus.net/index.php?act=ST&f=2&t=138429&view=old

本文介绍如何创建自己的代码证书(有CA证书签署的代码签名证书)

各位同学在自己动手操作之前请通篇阅读本文。尤其是各条注意事项。
不要看了前文不看后文就动手。否则很容易走上我曾经走过的弯路。

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