遍历元素

1:foreach 方式

// QList<outNode*> list;
foreach (outNode *i, list)
{if (i->sn == tmpNode->sn)
    {qDebug() << "find in list!";
    }
}

2:for 方式

// QList<outNode*> list;
for (int i = 0; i < list.size(); ++i)
{outNode *node = (outNode *)list.at(i);
    if (node->sn == tmpNode->sn)
    {qDebug() << "find in database!";
        list.removeAt(i);       // 删除
        list.append(tmpNode);   // 添加
        return;
    }
}