我正试图在另一个php while循环中执行php while循环，但当我到达第二个循环时，它不会返回到第一个循环并再次重新循环。以下是我正在使用的代码：
数据库连接字符串在一个单独的模块中。第一个while循环应该循环两次，但我认为当它到达第二个数据库while循环时发生的情况是，该循环返回正，它影响了第一个循环，所以我从第一个循环中只得到一个循环。有人能告诉我如何改变这一点以避免这个问题吗？
以下是来自数据库的两个循环：
while($row = $result->fetch_assoc()) {
// Show/Hide Regions:
error_reporting(-1);
ini_set('display_errors', 'On');
//Access our class.
$db_Class = new db_Class;
$conn = ($db_Class->db_conn());
$sql = "SELECT id, region FROM tbl_region;";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// output data of each row
$counter = 0; //Set count to 1
while($row = $result->fetch_assoc()) {
$counter++; //Increment counter by 1's
$rID = $row["id"];
?>
Output Region Here!
<?php
//Output companies for this region.
$sql = "SELECT
tbl_company.company_name,
tbl_company.group_number,
tbl_region.region
FROM
tbl_region
INNER JOIN tbl_company ON tbl_company.region_id = tbl_region.id
WHERE
$rID = tbl_company.region_id
ORDER BY
tbl_company.company_name ASC
";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
echo $row["company_name"]."<br>";
}
}
echo "A";
echo '</div>';
}
} ?>
使用任何其他名称更改内部循环$row和$result。。例如，我在这里做了$rowInner和$resultInner。
<?php
while($row = $result->fetch_assoc()) {
if ($result->num_rows > 0) {
$counter = 0; //Set count to 1
while($row = $result->fetch_assoc()) {
$counter++; //Increment counter by 1's
$rID = $row["id"];
?>
Output Region Here!
<?php
$sql = "SELECT
tbl_company.company_name,
tbl_company.group_number,
tbl_region.region
FROM
tbl_region
INNER JOIN tbl_company ON tbl_company.region_id = tbl_region.id
WHERE
$rID = tbl_company.region_id
ORDER BY
tbl_company.company_name ASC
";
$resultInner = $conn->query($sql);
if ($resultInner->num_rows > 0) {
while($rowInner = $resultInner->fetch_assoc()) { // Change $row to $rowInner
echo $rowInner["company_name"]."<br>";
}
}
echo "A";
echo '</div>';
}
}
}
?>
对于2 while循环，应该为$result使用不同的变量，如$result2。这就是造成冲突的原因。
您用第二个$row/$result覆盖了第一个$row$$result。请尝试为第二组结果使用其他名称。
// Show/Hide Regions:
error_reporting(-1);
ini_set('display_errors', 'On');
//Access our class.
$db_Class = new db_Class;
$conn = ($db_Class->db_conn());
$sql = "SELECT id, region FROM tbl_region;";
$result =
$conn->query($sql);
if ($result->num_rows > 0) {
// output data of each row
$counter = 0; //Set count to 1
while($row = $result->fetch_assoc()) {
$counter++; //Increment counter by 1's
$rID = $row["id"];
?>
Output Region Here!
<?php
//Output companies for this region.
$sql = "SELECT
tbl_company.company_name,
tbl_company.group_number,
tbl_region.region
FROM
tbl_region
INNER JOIN tbl_company ON tbl_company.region_id = tbl_region.id
WHERE
$rID = tbl_company.region_id
ORDER BY
tbl_company.company_name ASC
";
$result2 = $conn->query($sql);
if ($result2->num_rows > 0) {
// output data of each row
while($row2 = $result2->fetch_assoc()) {
echo $row2["company_name"]."<br>";
}
}
echo "A";
echo '</div>';
}
} ?>
您应该为内部和外部while循环使用不同的变量。尝试以下操作：
<?php
// Show/Hide Regions:
error_reporting(-1);
ini_set('display_errors', 'On');
//Access our class.
$db_Class = new db_Class;
$conn = ($db_Class->db_conn());
$sql = "SELECT id, region FROM tbl_region;";
$resultOuter = $conn->query($sql);
if ($resultOuter->num_rows > 0)
{
// output data of each row
$counter = 0; //Set count to 1
while($rowOuter = $resultOuter->fetch_assoc())
{
$counter++; //Increment counter by 1's
$rID = $rowOuter["id"];
//Output companies for this region.
$sql = "SELECT tbl_company.company_name, tbl_company.group_number, tbl_region.region
FROM tbl_region
INNER JOIN tbl_company ON tbl_company.region_id = tbl_region.id
WHERE
$rID = tbl_company.region_id
ORDER BY
tbl_company.company_name ASC ";
$resultInner = $conn->query($sql);
if ($resultInner->num_rows > 0)
{
// output data of each row
while($rowInner = $resultInner->fetch_assoc())
{
echo $rowInner["company_name"]."<br>";
}
}
echo "A";
echo '</div>';
}
}
?>