問題描述

我正在從 mysql 數據庫中檢索一些數據.有兩個循環使用相同的結果集.

I'm retrieving some data from a mysql database. There are two loops which uses the same result set.

while ($row = mysqli_fetch_array($newsQuery)) {
     echo "<a href='news-article.php?articleId=" .$row["news_id"]."' class='list-group-item active'>".$row["news_title"]."</a>";
}

這個循環以成功結束.然后在同一頁面中，我有以下循環.

This loop ends with success. then in the same page I have the following loop.

while ($row = mysqli_fetch_array($newsQuery)) {
    echo $row["news_content"];
}

即使表中有內容，此循環也不會返回任何內容.當我在第一個循環中嘗試時.內容顯示正確.知道我做錯了什么.

This loop doesn't return anything even if there are content in the table. When I try it in the first loop. the content is displayed correctly. Any idea on what I'm doing wrong.

推薦答案

來自 PHP 的 mysqli_fetch_array DOCS:

From PHP's mysqli_fetch_array DOCS:

返回一個與獲取的行相對應的數組，如果 result 參數表示的結果集沒有更多行，則返回 NULL.

Returns an array that corresponds to the fetched row or NULL if there are no more rows for the resultset represented by the result parameter.

您在 $row = mysqli_fetch_array($newsQuery)

這意味著循環將繼續進行，直到 mysqli_fetch_array($newsQuery) 返回 NULL.

This means the loop will keep going untill mysqli_fetch_array($newsQuery) returns NULL.

這就是您不能再次使用該循環的原因，因為 mysqli 已完成獲取結果并且 mysqli_fetch_array($newsQuery) 現在返回 NULL 直到您進行新查詢.

This is the reason why you cant use that loop again, since mysqli has finished fetching the results and the mysqli_fetch_array($newsQuery) now returns NULL untill you make a new query.

嘗試先用結果填充一個變量，然后在該變量上循環:

Try populating a variable with the results first, then loop on that variable:

$results = array();
while ($row = mysqli_fetch_array($newsQuery)) {
     $results[] = $row;
}

foreach ($results as $key => $row) {
    echo "<a href='news-article.php?articleId=" .$row["news_id"]."' class='list-group-item active'>".$row["news_title"]."</a>";
}


foreach ($results as $key => $row) {
    echo $row["news_content"];
}

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