在MySQL服务器上重新连接已经消失

Question

如何修改此类以捕获MySQL Server离开的异常并重新连接？

<?php
class DBConn
{
private $conn;

public function __construct( $persistent = false )
{
    try
    {
        $this->conn = new PDO( "mysql:host=localhost;dbname=test", 'test', "hoollaahaoo" );
        $this->conn->exec( "SET CHARACTER SET utf8" );
        $this->conn->setAttribute( PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC ); 
        if ( $persistent )
            $this->conn->setAttribute( PDO::ATTR_PERSISTENT, true );
    }
    catch( PDOException $e )
    {
        return $e->getMessage();
    }
}

public function getConn()
{
    return $this->conn;
}
}

Answer 1

你可能需要像这样创建自己的类

1. 从try/except
中移除__construct
2. 然后连接到你这样的数据库：

$conn = null;
$limit = 10;
$counter = 0;
while (true) {
  try {
    $conn = DBConn();
    break;
  }
  catch (Exception $e) {
    $conn = null;
    $counter++;
    if ($counter == $limit)
      throw $e;
  }

}

编辑1 ：

但如果你说你的服务器消失了......那么可能就像这样

protected function _connect( $persistent = false ) {
$conn = null;
$limit = 10;
$counter = 0;
while (true) {
  try {
        $this->conn = new PDO( "mysql:host=localhost;dbname=test", 'test', "hoollaahaoo" );
        $this->conn->exec( "SET CHARACTER SET utf8" );
        $this->conn->setAttribute( PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC ); 
        if ( $persistent )
            $this->conn->setAttribute( PDO::ATTR_PERSISTENT, true );
}
  catch (Exception $e) {
    $conn = null;
    $counter++;
    if ($counter == $limit)
      throw $e;
  }
}

public function __construct( $persistent = false )
{
    $this->_connect($persistent);
}