您能在迭代過程中從std：list中刪除元素嗎？我有這樣的代碼：for (std::list<item*>::iterator i=items.begin();i!=items.end();i++){
bool isActive = (*i)->update();
//if (!isActive)
// items.remove(*i);
//else
other_code_involving(*i);}items.remove_if(CheckItemNotActive);我希望在更新后立即刪除不活動的項目，以避免再次瀏覽列表。但是，如果我添加注釋行，當我到達i++*“列表迭代器不可遞增”。我嘗試了一些沒有在for語句中增加的交替語句，但是我沒有得到任何工作。在您行走STD：List時，刪除項目的最佳方法是什么？
3 回答
忽然笑
TA貢獻1806條經驗 獲得超5個贊
std::list<item*>::iterator i = items.begin();while (i != items.end()){
bool isActive = (*i)->update();
if (!isActive)
{
items.erase(i++); // alternatively, i = items.erase(i);
}
else
{
other_code_involving(*i);
++i;
}}
江戶川亂折騰
TA貢獻1851條經驗 獲得超5個贊
// Note: Using the pre-increment operator is preferred for iterators because// there can be a performance gain.//// Note: As long as you are iterating from beginning to end, without inserting// along the way you can safely save end once; otherwise get it at the// top of each loop.std::list< item * >::iterator iter = items.begin();std::list< item * >::iterator end = items.end();while (iter != end){
item * pItem = *iter;
if (pItem->update() == true)
{
other_code_involving(pItem);
++iter;
}
else
{
// BTW, who is deleting pItem, a.k.a. (*iter)?
iter = items.erase(iter);
}}// This implementation of update executes other_code_involving(Item *) if// this instance needs updating.//// This method returns true if this still needs future updates.//bool Item::update(void){
if (m_needsUpdates == true)
{
m_needsUpdates = other_code_involving(this);
}
return (m_needsUpdates);}// This call does everything the previous loop did!!! (Including the fact// that it isn't deleting the items that are erased!)items.remove_if(std::not1(std::mem_fun(&Item::update)));- 3 回答
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