PHP实现货币换算的方法

本文实例讲述了PHP实现货币换算的方法。分享给大家供大家参考。

具体实现代码如下：
代码如下:<?php
/*
* File: CurrencyConverter.php
* Author: Simon Jarvis
* Copyright: 2005 Simon Jarvis
* Date: 10/12/05
* Link: http://www.white-hat-web-design.co.uk/articles/php-currency-conversion.php
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details:
* http://www.gnu.org/licenses/gpl.html
*
*/
class CurrencyConverter {
   var $xml_file = "www.ecb.int/stats/eurofxref/eurofxref-daily.xml";
   var $mysql_host, $mysql_user, $mysql_pass, $mysql_db, $mysql_table;
   var $exchange_rates = array();
   //Load Currency Rates
   function CurrencyConverter($host,$user,$pass,$db,$tb) {
      $this->mysql_host = $host;
      $this->mysql_user = $user;
      $this->mysql_pass = $pass;
      $this->mysql_db = $db;
      $this->mysql_table = $tb;
      $this->checkLastUpdated();
      $conn = mysql_connect($this->mysql_host,$this->mysql_user,$this->mysql_pass);
      $rs = mysql_select_db($this->mysql_db,$conn);
      $sql = "SELECT * FROM ".$this->mysql_table;
      $rs =  mysql_query($sql,$conn);
      while($row = mysql_fetch_array($rs)) {
         $this->exchange_rates[$row['currency']] = $row['rate'];
      }
   }
   /* Perform the actual conversion, defaults to £1.00 GBP to USD */
   function convert($amount=1,$from="GBP",$to="USD",$decimals=2) {
      return(number_format(($amount/$this->exchange_rates[$from])*$this->exchange_rates[$to],$decimals));
   }
   /* Check to see how long since the data was last updated */
   function checkLastUpdated() {
      $conn = mysql_connect($this->mysql_host,$this->mysql_user,$this->mysql_pass);
      $rs = mysql_select_db($this->mysql_db,$conn);