PHP基于MySQLI函数封装的数据库连接工具类

本文实例讲述了PHP基于MySQLI函数封装的数据库连接工具类。分享给大家供大家参考，具体如下：

mysql.class.php：

mysqli = new mysqli($host, $username, $password, $database, $port);
  }
  
  public function select($table, $field = null, $where = null)
  {
    $sql = "SELECT * FROM {$table}";
    if (!empty($field)) {
      $field = '`' . implode('`,`', $field) . '`';
      $sql = str_replace('*', $field, $sql);
    }
    if (!empty($where)) {
      $sql = $sql . ' WHERe ' . $where;
    }
    $this->result = $this->mysqli->query($sql);
    return $this->result->num_rows;
  }
  
  public function fetchAll()
  {
    return $this->result->fetch_all(MYSQLI_ASSOC);
  }
  
  public function insert($table, $data)
  {
    foreach ($data as $key => $value) {
      $data[$key] = $this->mysqli->real_escape_string($value);
    }
    $keys = '`' . implode('`,`', array_keys($data)) . '`';
    $values = ''' . implode("','", array_values($data)) . ''';
    $sql = "INSERT INTO {$table}( {$keys} )VALUES( {$values} )";
    $this->mysqli->query($sql);
    return $this->mysqli->insert_id;
  }
  
  public function update($table, $data, $where)
  {
    foreach ($data as $key => $value) {
      $data[$key] = $this->mysqli->real_escape_string($value);
    }
    $sets = array();
    foreach ($data as $key => $value) {
      $kstr = '`' . $key . '`';
      $vstr = ''' . $value . ''';
      array_push($sets, $kstr . '=' . $vstr);
    }
    $kav = implode(',', $sets);
    $sql = "UPDATE {$table} SET {$kav} WHERe {$where}";
    $this->mysqli->query($sql);
    return $this->mysqli->affected_rows;
  }
  
  public function delete($table, $where)
  {
    $sql = "DELETE FROM {$table} WHERe {$where}";
    $this->mysqli->query($sql);
    return $this->mysqli->affected_rows;
  }
}

使用方法

 'mysql',
  'host' => 'localhost',
  'username' => 'woider',
  'password' => '3243',
  'database' => 'php',
  'port' => '3306'
);

$mysql = new mysql();
$mysql->connect($config);

//1、查询所有数据
$table = 'mysqli';//数据表
$num = $mysql->select($table);
echo '共查询到' . $num . '条数据';
print_r($mysql->fetchAll());
//2、查询部分数据
$field = array('username', 'password'); //过滤字段
$where = 'id % 2 =0';   //过滤条件
$mysql->select($table, $field, $where);
print_r($mysql->fetchAll());

$table = 'mysqli';//数据表
$data = array(  //数据数组
  'username' => 'admin',
  'password' => sha1('admin')
);
$id = $mysql->insert($table, $data);
echo '插入记录的ID为' . $id;

$table = 'mysqli';//数据表
$data = array(
  'password' => sha1('nimda')
);
$where = 'id = 44';
$rows = $mysql->update($table, $data, $where);
echo '受影响的记录数量为' . $rows . '条';

$table = 'mysqli';
$where = 'id = 45';
$rows = $mysql->delete($table, $where);
echo '已删除' . $rows . '条数据';

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希望本文所述对大家PHP程序设计有所帮助。