Question

我目前正在获取项目中有3个数据的教堂清单，但是问题是当我尝试循环while时它会无限循环，而当var_dump仅显示1个数据时。但是当我使用PDO时，它可以正常工作。

这是我的数据库类

<?php
namespace classes\worker;

use \mysqli;

const DB_HOST = 'localhost';
const DB_USERNAME = 'root';
const DB_PASSWORD = '';
const DB_NAME = 'db_sk';

class Database {
    public function __construct() {
        $this->db = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD, DB_NAME);

        if($this->db->connect_error) {
            die($this->db->connect_error);
        }
    }

    protected function select($table, $condition = '', $column = '*') {
        $condition = ($condition == '') ? '' : ' WHERE ' . $condtion;

        $query = 'SELECT ' . $column . ' FROM ' . $table . $condition . ';';

        $sth = $this->db
                    ->query($query);

        if($sth) {
            return $sth;
        } else {
            return $this->db
                        ->error;
        }
    }

    protected function insert($table, array $data) {
        ksort($data);

        $column = join(', ', array_keys($data));
        $values = '"' . join('", "', array_values($data)) . '"';

        $query = 'INSERT INTO ' . $table . '(' . $column . ') VALUES(' . $values . ');';

        $sth = $this->db
                    ->query($query);

        if($sth) {
            return $this->db
                        ->insert_id;
        } else {
            return $this->db
                        ->error;
        }
    }

    protected function update($table, array $data, $condition) {
        ksort($data);

        $set = '';

        foreach($data as $keys => $values) {
            $set .= $keys . '="' . $values . '", ';
        }

        $set = rtrim($set, ', ');

        $query = 'UPDATE ' . $table . ' SET ' . $set . ' WHERE ' . $condition . ';';

        $sth = $this->db
                    ->query($query);

        if($sth) { return true; } else { return false; }
    }

    protected function delete($table, $condition) {
        $query = 'DELETE FROM ' . $table . ' WHERE ' . $condition . ';';

        $sth = $this->db
                    ->query($query);

        if($sth) { return true; } else { return false; }
    }
}

这是我的教堂课

<?php
namespace classes\helper;

use \classes\worker\{Database};

final class Church extends Database {
    public function getChurch() : object {
        return $this->select('tbl_church_info', '', 'acc_id, name');
    }
}

这是我测试结果的页面：

<?php 
    use \classes\helper\{Church}; 

    $church = (new Church())->getChurch();

    var_dump($church); // only show 1 data but has 3 data in database

    while(($row = $church->fetch_assoc()) !== NULL) {
       echo $row['acc_id']; 
    } // which loop infinite

?>

Answer 1

这是因为您仅调用一次fetch_assoc

   $church = (new Church())->getChurch()->fetch_assoc();
    var_dump($church); // only show 1 data but has 3 data in database
    while(($row = $church)) {
       echo $row['acc_id']; 
   } // which

可能在哪里

   $church = new Church();
    while($row = $church->getChurch()->fetch_assoc()) {
       echo $row['acc_id']; 
    } // which

类似的问题在这里MySQL fetch_assoc() shows 1 less result

Answer 2

我所做的解决方案就是这样。在教会类中，我已经返回了结果。

<?php
namespace classes\helper;

use \classes\worker\{Database};

final class Church extends Database {
    public function getChurch() : array {
        $selected = $this->select('tbl_church_info', '', 'acc_id, name');

        while(($row = $selected->fetch_assoc()) !== NULL) {
          $tmp[] = $row;
        }

        return $tmp;
    }
}

然后我很容易看到结果的输出，

<?php 
    use \classes\helper\{Church}; 

    $church = new Church();

    foreach($church->getChurch as $list) {
      var_dump($list); // and works properly :)
    }

?>

FETCH_ASSOC仅显示1个数据并无限循环显示PHP

2 个答案: