void CTest_1AppUi::HandleCommandL(TInt aCommand)
    {
    switch ( aCommand )
        {
        case EAknSoftkeyBack:
        case EEikCmdExit:
            {
                  _LIT(KQueryDelete,"Are you sure to delete it?");
                  CAknQueryDialog* dlg = new(ELeave) CAknQueryDialog(const_cast<TDesC&>(KQueryDelete()),CAknQueryDialog::EWarningTone);

                  TInt temp = dlg->ExecuteLD(R_DIALOG_DELETE_QUERY);

                  _LIT(KReturnValue,"the return value is :");

                  HBufC* iBuf = HBufC::NewLC(100);
                  iBuf->Des().Copy(KReturnValue);
                  iBuf->Des().AppendNum(temp);
                  CEikonEnv::Static()->InfoMsg(*iBuf);
                  CleanupStack::PopAndDestroy(iBuf);
                  break;
            }

        default:
            break;     
        }
    }

           从程序执行中我们可以看到,当我们点dlg的NO按钮时,temp的值为一个正数(程序中是3005),而当我们点dlg 的OK的时候,temp的值为0。

           所以我们在很多程序中可以看到类似下面的代码:

if(dlg->ExecuteLD(R_DIALOG_DELETE_QUERY))
    {
        TInt index = iListBox->CurrentItemIndex();
        TName name(db.iName);
        iUi->iDB->iArrayDB->Delete(index);
        iUi->iDB->SaveDBL();
        CEikonEnv::Static()->ReadResource(info, R_STR_DELETE_TIPS);
        tips.Format(info, &name);
        ShowNotify(tips);
        if(iUi->iDB->iArrayDB->Count()==0)
        {
            CEikonEnv::Static()->ReadResource(info, R_STR_NO_CD_TIPS);
            ShowNotify(info);
            CreateFunctionListBoxL();
        }
        else
        {
            CreateRecordListBoxL();
        }
    }

也就是判断我们是否点击了Dialog的OK按钮。