在A While循环中执行PHP While循环

Question

我试图在另一个php while循环中执行php while循环，但是当我进入第二个循环时，它不会返回到第一个循环，而是再次循环--下面是我使用的代码：

数据库连接字符串位于单独的模块中。第一个while循环应该循环两次，但是当它到达第二个数据库while循环时会发生什么，这个循环返回正，它会影响第一个循环，所以我只从第一个循环得到一个循环。谁能告诉我怎样才能改变这个问题以避免这个问题？

以下是数据库中的两个循环：

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>';
            }
            } ?>

Answer 1

用我在这里做过的任何其他$row和$resultInner示例更改内环name..for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>';
        }
    }
} 
?>

Answer 2

对于$result，您应该使用一个不同的变量，比如2 like循环的$result2。这导致了冲突。

Answer 3

您用第二个$行/$结果覆盖了第一个$行/$结果。尝试为第二组结果使用不同的名称。

// 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>';
    }
    } ?>