IADsPropertyValue：：Clear 方法 (iads.h)

IADsPropertyValue：：Clear 方法清除属性值对象的当前值。

语法

HRESULT Clear();

返回值

此方法支持标准 HRESULT 返回值，包括S_OK。 有关详细信息和其他返回值，请参阅 ADSI 错误代码。

备注

无

示例

下面的代码示例演示如何使用 IADsPropertyValue：：Clear 从属性列表中清除“description”属性的值。

Dim propList As IADsPropertyList
Dim propEntry As IADsPropertyEntry
Dim propVal As IADsPropertyValue

On Error GoTo Cleanup
 
' Get the property list.
Set propList = GetObject("LDAP://dc01/DC=Fabrikam,DC=com")
propList.GetInfo
 
' Get a property entry. If you know the exact type of the property,
' replace ADSTYPE_UNKNOWN with that type.
Set propEntry = propList.GetPropertyItem("description", ADSTYPE_UNKNOWN)
 
' Clear all the values of the property entry.
For Each v In propEntry.Values
    Set propVal = v
    propVal.Clear
Next

propList.SetInfo

Cleanup:
    If (Err.Number<>0) Then
        MsgBox("An error has occurred. " & Err.Number)
    End If

    Set propList = Nothing
    Set propEntry = Nothing
    Set propVal = Nothing

下面的代码示例演示如何使用 IADsPropertyValue：：Clear 从属性列表中清除“description”属性的值。

#include <activeds.h>
#include <stdio.h>
 
IADsPropertyList *pList = NULL;
IADsPropertyEntry *pEntry = NULL;
IADsPropertyValue *pVal = NULL;
IADs *pObj = NULL;
VARIANT var, varItem;
BSTR valStr;
IEnumVARIANT *pEnum = NULL;
LONG lstart, lend;
 
VariantInit(&var);
VariantInit(&varItem);
 
// Bind to the directory object.
HRESULT hr = ADsGetObject(L"LDAP://dc01/DC=Fabrikam,DC=com",
                          IID_IADsPropertyList,
                          (void**)&pList);
if(FAILED(hr)){goto Cleanup;}

 
// Initialize the property cache.
hr = pList->QueryInterface(IID_IADs,(void**)&pObj);
if(FAILED(hr)){goto Cleanup;}

pObj->GetInfo();
pObj->Release();
 
// Get a property entry.
hr = pList->GetPropertyItem(CComBSTR("description"), ADSTYPE_UNKNOWN, &var);
if(FAILED(hr)){goto Cleanup;}

pList->Release();
hr = V_DISPATCH(&var)->QueryInterface(IID_IADsPropertyEntry,
                                      (void**)&pEntry);
if(FAILED(hr)){goto Cleanup;}
VariantClear(&var);
 
// Get the value array of the property entry.
hr = pEntry->get_Values(&var);
if(FAILED(hr)){goto Cleanup;}
SAFEARRAY *sa = V_ARRAY( &var );
 
// Get the lower and upper bound, iterate, and print the values.
hr = SafeArrayGetLBound( sa, 1, &lstart );
hr = SafeArrayGetUBound( sa, 1, &lend );
printf(" Property value(s) = ");
for ( long idx=lstart; idx < lend+1; idx++ )    {
    hr = SafeArrayGetElement( sa, &idx, &varItem );
    hr = V_DISPATCH(&varItem)->QueryInterface(IID_IADsPropertyValue,
                                              (void**)&pVal);
    VariantClear(&varItem);
    hr = pVal->Clear();
    if(FAILED(hr)){goto Cleanup;}
}

pList->SetInfo();

Cleanup:
    if(pList)
        pList->Release();

    if(pEntry)
        pEntry->Release();

    if(pVal)
        pVal->Release();

    if(pObj)
        pObj->Release();

    if(pEnum)
        pEnum->Release();

    if(valStr)
        SysFreeString(valStr);

    VariantClear(&var);
    VariantClear(&varItem);

要求

要求	值
最低受支持的客户端	Windows Vista
最低受支持的服务器	Windows Server 2008
目标平台	Windows
标头	iads.h
DLL	Activeds.dll

另请参阅

ADSI 错误代码

IADsPropertyValue

IADsPropertyValue 属性方法