javascript - 如何在刷新时保持我在页面上的位置(AJAX)

Question

我知道这只能通过 AJAX 实现，但我从未使用过 AJAX...在我的网站上，您可以保留游戏 Magic 中的卡牌列表，这就是完整的列表。您必须按一个按钮才能添加卡片，每张卡片都有这个按钮，当您添加它时，它会将卡片添加到您的列表中，然后刷新并再次位于页面顶部。我怎样才能让它保持它的位置？

在红色方 block 内，您可以按添加或删除:http://prntscr.com/5uq6ak

Functions.php(我只会显示 2 个函数，删除和添加卡片)

//Add card to collection
function addCardToCollection($conn, $userID, $cardID){
//Checks if the cards is already added for this user
    $queryGetCard = 'SELECT user_id, card_id FROM collection WHERE user_id = '.$userID.' AND card_id = '.$cardID;
    $checkCollection = $conn->query($queryGetCard);
    if($checkCollection->fetch_assoc() > 0){return 'Deze kaart hebt u al.';}

//Adds card to the database
    $queryAddCard = 'INSERT INTO collection (user_id, card_id) VALUES ('.$userID.','.$cardID.')';
    if($conn->query($queryAddCard)){return 'Kaart toegevoegd.';}
    else{return 'Kaart niet toegevoegd.';}
}

//Remove card from collection
function removeCardFromCollection($conn, $userID, $cardID){
//Checks if the cards is in the collection
    $queryGetCard = 'SELECT user_id, card_id FROM collection WHERE user_id = '.$userID.' AND card_id = '.$cardID;
    $checkCollection = $conn->query($queryGetCard);
    if($checkCollection->fetch_assoc() == 0){return 'Deze kaart hebt u nog niet.';}

//Remove card from the database
    $queryAddCard = 'DELETE FROM collection WHERE user_id = '.$userID.' AND card_id = '.$cardID;
    if($conn->query($queryAddCard)){return 'Kaart verwijderd uit uw collectie.';}
    else{return 'Kaart niet verwijderd uit uw collectie.';}
}

Set.php(添加和删除按钮)

if(login_check($mysqli) == true) {
    $cardsHTML.='<br><b>Deze kaart heb ik...
    <a href="' . $baseURL . 'set.php?id=' . $_GET['id'] . '&cardID=' . $value['id'] . '&collection=add">
        <div class="glyphicon glyphicon-ok green"></div>
    </a> |
    <a href="' . $baseURL . 'set.php?id=' . $_GET['id'] . '&cardID=' . $value['id'] . '&collection=remove">
        <div class="glyphicon glyphicon-remove red"></div>
    </a>
    </b>';
}

Answer 1

在插入期间添加带有时间戳的列。 并获取时间戳升序的数据。 显示卡片。它不会改变。