我有下面的代码，并试图从我的 sql 表中获取接下来的 25 个结果以显示在页面上。 但是，每当我单击下一步按钮时，都不会显示任何信息。 我有我的偏移量 = （$page - 1） * $items_per_page......我正在努力弄清楚这一点，因为与我编写的其他代码相比，它似乎很简单，但事实证明对我来说非常难以捉摸......任何协助将不胜感激。 我的主要问题是下一个链接没有提供接下来的 25 个结果，我无法确定为什么以及如何更正。
echo "<h3 style='text-align:center;'>Welcome to the Exchange Portal, " . $row['name'] . "! </h3>";
$items_per_page = 25;
$sql_count = "SELECT pin, title, title2, email, phone FROM crown_acura";
$result_cnt = mysqli_query($conn, $sql_count);
if(false === $result_cnt) {
throw new Exception('Query failed with: ' . mysqli_error());
} else {
$row_count = mysqli_num_rows($result_cnt);
// free the result set as you don't need it anymore
//mysqli_free_result($result_cnt);
}
echo $row_count;
echo " ";
if (!isset($_GET['Page'])) {
$Page = 1;
} else {
$Page = $_GET['Page'];
}
echo $page;
echo " ";
$page_count = 0;
if (0 === $row_count) {
// maybe show some error since there is nothing in your table
} else {
// determine page_count
$page_count = (int)ceil($row_count / $items_per_page);
// double check that request page is in range
if($page > $page_count) {
// error to user, maybe set page to 1
$page = 1;
}
}
echo " ";
echo $page_count;
echo " ";
echo $items_per_page;
$offset = ($page-1)*$items_per_page;
//echo $paging_info;
//echo " ";
echo "<br />";
//Query for displaying results
$list_sql = "SELECT pin, title, title2, email, phone FROM crown_acura LIMIT $offset, $items_per_page";
$result_query = $conn->query($list_sql);
//Table for displaying query results
echo "<table class='verify'>";
echo "<tr >";
echo "<td><h3>Name</h3></td><td> </td><td><h3>E-mail</h3></td><td><h3>Phone</h3></td>";
echo "</tr>";
for($i = 1; $i<= $page_count; $i++) {
if ($result_query->num_rows > 0) {
// output data of each row
while($row3 = mysqli_fetch_array($result_query)) {
echo "<tr>";
echo "<td class='dltd2 dlcl'>" . $row3["title"] . "</td><td>" . $row3["title2"] . "</td><td><a href='mailto:" . $row3['email'] . "'>" . $row3["email"] . "</a> </td><td>" . $row3["phone"] . " </td>";
echo "</tr>";
}
} else {
echo "0 results";
}
}
echo "<tr></tr>";
$next_page = $page + 1;
$last_page = $page - 1;
if($paging_info['curr_page'] <= 1) {
echo "<tr>";
echo "<td></td><td colspan='2'><a class='loadlink' href='" . $_PHP_SELF . "'>Next 25</a></td><td></td>";
echo "</tr>";
} elseif ($paging_info['curr_page'] < $page_count) {
echo "<tr>";
echo "<td></td><td><a href='" . $_PHP_SELF . "?page=" . $last_page . "'>Prev 25</a></td><td><a href='" . $_PHP_SELF . "?page=" . $next_page . "'>Next 25</a></td><td></td>";
echo "</tr>";
} elseif ($paging_info['curr_page'] === $page_count) {
echo "<tr>";
echo "<td></td><td colspan='2'><a href='" . $_PHP_SELF . "?page=" . $last_page . "'>Prev 25</a></td><td></td>";
echo "</tr>";
}
echo "</table>";
}
}
}
您是否尝试运行渲染的 SQL。
输出到浏览器：
"SELECT pin, title, title2, email, phone FROM crown_acura LIMIT $offset, $items_per_page"
试试这个...并更改不同值（2，3,...,等）的$page
<?php
$items_per_page = 25;
$sql_count = "SELECT pin, title, title2, email, phone FROM crown_acura";
$result_cnt = mysqli_query($conn, $sql_count);
if (false === $result_cnt) {
throw new Exception('Query failed with: ' . mysqli_error());
} else {
$row_count = mysqli_num_rows($result_cnt);
// free the result set as you don't need it anymore
//mysqli_free_result($result_cnt);
}
echo $row_count;
echo " ";
if (!isset($_GET['Page'])) {
$Page = 1;
} else {
$Page = $_GET['Page'];
}
echo $page;
echo " ";
$page_count = 0;
if (0 === $row_count) {
// maybe show some error since there is nothing in your table
} else {
// determine page_count
$page_count = (int)ceil($row_count / $items_per_page);
// double check that request page is in range
if ($page > $page_count) {
// error to user, maybe set page to 1
$page = 1;
}
}
echo " ";
echo $page_count;
echo " ";
echo $items_per_page;
$offset = ($page - 1) * $items_per_page;
//echo $paging_info;
//echo " ";
echo "<br />";
//Query for displaying results
$list_sql = "SELECT pin, title, title2, email, phone FROM crown_acura LIMIT $offset, $items_per_page";
$result_query = $conn->query($list_sql);
echo ("RESULTS: ".$result_query->num_rows());
？>