IADs::Get method

The IADs::Get method retrieves a property of a given name from the property cache. The property can be single-valued, or multi-valued. The property value is represented as either a variant for a single-valued property or a variant array (of VARIANT or bytes) for a property that allows multiple values.

Syntax


HRESULT Get(
  [in]   BSTR bstrName,
  [out]  VARIANT *pvProp
);

Parameters

bstrName [in]

Contains a BSTR that specifies the property name.

pvProp [out]

Pointer to a VARIANT that receives the value of the property. For a multi-valued property, pvProp is a variant array of VARIANT, unless the property is a binary type. In this latter case, pvProp is a variant array of bytes (VT_U1 or VT_ARRAY). For the property that refers to an object, pvProp is a VT_DISPATCH pointer to the object referred to.

Return value

This method supports standard return values, as well as the following.

For more information, see ADSI Error Codes.

Return codeDescription
S_OK

The property value was retrieved successfully.

E_ADS_PROPERTY_NOT_FOUND

The property was not found in the cache. The property may not have an attribute, or is invalid.

E_FAIL

The operation failed.

 

Remarks

The IADs::Get method requires the caller to handle the single- and multi-valued property values differently. Thus, if you know that the property of interest is either single- or multi-valued, use the IADs::Get method to retrieve the property value. The following code example shows how you, as a caller, can handle single- and multi-valued properties when calling this method.

When a property is uninitialized, calling this method invokes an implicit call to the IADs::GetInfo method. This loads from the underlying directory store the values of the supported properties that have not been set in the cache. Any subsequent calls to IADs::Get deals with property values in the cache only. For more information about the behavior of implicit and explicit calls to IADs::GetInfo, see IADs::GetInfo.

You can also use IADs::GetEx to retrieve property values from the property cache. However, the values are returned as a variant array of VARIANTs, regardless of whether they are single-valued or multi-valued. That is, ADSI attempts to package the returned property values in consistent data formats. This saves you, as a caller, the effort of validating the data types when unsure that the returned data has single or multiple values.

Examples

The following code example retrieves the security descriptor for an object using IADs::Get.


Dim x As IADs
Dim Desc As IADsSecurityDescriptor
On Error GoTo ErrTest:
 
Set x = GetObject("LDAP://CN=Administrator,CN=Users,DC=Fabrikam,DC=com")
 
' Single-valued properties.
Debug.Print "Home Phone Number is: " & x.Get("homePhone")
 
' Some property values represents other ADSI objects. 
' Consult your provider documentation.
Set Desc = x.Get("ntSecurityDescriptor")
 
' Multi-valued property, assuming that multiple values were
' assigned to the "otherHomePhone" properties. Caller must 
' enumerate all the available values.
Debug.Print "Other Phone Numbers are: "
otherNumbers = x.Get("otherHomePhone")
For Each homeNum In otherNumbers
  Debug.Print homeNum
Next
 
Exit Sub
 
ErrTest:
  Debug.Print Hex(Err.Number)
  Set x = Nothing
  Set Desc = Nothing

The following code example shows how to work with property values of binary data using IADs::Get and IADs::Put.


Dim oTarget As IADs
Dim Octet(5) As Byte
Dim MultiOctet(2) As Variant
Dim i As Integer, j As Integer

On Error GoTo Cleanup
 
' Set up MultiOctetString.
For i = 0 To 2
    For j = 0 To 5
        Octet(j) = CByte(i * j)
    Next j
    MultiOctet(i) = Octet
Next i
 
' Bind to the object and set MultiOctetString.
Set oTarget=GetObject("LDAP://CN=SomeUser,CN=Users,DC=Fabrikam, DC=COM")
oTarget.Put "multiOctetString", MultiOctet
oTarget.SetInfo
 
Dim GetOctet As Variant
Dim Temp As Variant
 
' Read back and print MultiOctetString.
GetOctet = oTarget.Get("multiOctetString")
For i = LBound(GetOctet) To UBound(GetOctet)
    Temp = GetOctet(i)
    For j = LBound(Temp) To UBound(Temp)
        Debug.Print Temp(j)
    Next j
    Debug.Print "----"
Next i

Exit Sub

Cleanup:
   MsgBox("An error has occurred. " & Err.Number)
   Set oTarget = Nothing

The following code example shows how to retrieve values of the optional properties of an object using IADs::Get.


<HTML>
<head><title></title></head>

<body>
<%
Dim x 
 
On error resume next
Set x = GetObject("WinNT://Fabrikam/Administrator")
Response.Write "Object Name: " & x.Name & "<br>"
Response.Write "Object Class: " & x.Class & "<br>"
 
' Get optional property values of this object.
Set cls = GetObject(x.Schema)

For Each op In cls.OptionalProperties
   v = obj.Get(op)
   if err.Number = 0 then
       Response.Write "Optional Property: " & op & "=" & v & "<br>"
   end if
Next
%>

</body>
</html>

The following code example reads attributes with single and multiple values using IADs::Get.


HRESULT hr;
IADs *pUsr=NULL;
 
CoInitialize(NULL);
 
///////////////////////////////
// Bind to a directory object.
///////////////////////////////
hr = ADsGetObject(L"WinNT://Fabrikam/Administrator,user", IID_IADs, (void**) &pUsr );
if ( !SUCCEEDED(hr) ) { return hr; }
 
//////////////////////////////////
// Get a single-valued attribute.
//////////////////////////////////
VARIANT var;
VariantInit(&var);
 
hr = pUsr->Get(CComBSTR("FullName"), &var );
if ( SUCCEEDED(hr) )
{
    printf("FullName: %S\n", V_BSTR(&var) );
    VariantClear(&var);
}
 
if ( pUsr )
{
    pUsr->Release();
}
 
///////////////////////////////////////////////////////
// Get a multi-valued attribute from a service object.
///////////////////////////////////////////////////////
IADs *pSvc = NULL;
 
hr = ADsGetObject(L"WinNT://Fabrikam/Account/Browser,service", IID_IADs, (void**) &pSvc );
if ( !SUCCEEDED(hr) )
{
    return hr;
}
 
hr = pSvc->Get(CComBSTR("Dependencies"), &var );
if ( SUCCEEDED(hr) )
{
    LONG lstart, lend;
    SAFEARRAY *sa = V_ARRAY( &var );
    VARIANT varItem;
 
    // Get the lower and upper bound.
    hr = SafeArrayGetLBound( sa, 1, &lstart );
    hr = SafeArrayGetUBound( sa, 1, &lend );
 
    // Iterate and print the content.
    VariantInit(&varItem);
    printf("Getting service dependencies using IADs :\n");
    for ( long idx=lstart; idx <= lend; idx++ )
    {
        hr = SafeArrayGetElement( sa, &idx, &varItem );
        printf("%S ", V_BSTR(&varItem));
        VariantClear(&varItem);
    }
    printf("\n");
 
    VariantClear(&var);
}
 
// Cleanup.
if ( pSvc )
{
    pSvc->Release();
}

Requirements

Minimum supported client

Windows Vista

Minimum supported server

Windows Server 2003

Header

Iads.h

DLL

Activeds.dll

IID

IID_IADs is defined as FD8256D0-FD15-11CE-ABC4-02608C9E7553

See also

IADs
IADs::GetEx
IADs::GetInfo
Property Cache
IADs::Put
IADs::PutEx

 

 

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