【ext js 学习笔记】获取后台返回的自定义错误信息

突然发现某位大侠的管理后台是用EXT JS写的，让我觉得效果非常炫，所以自己也开始自学EXT JS。

做了一个DEMO，功能主要是前台页面获取后台返回的自定义的错误信息。

本DEMO需要自己下EXT的框架包。

页面demo.html：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh" lang="zh" dir="ltr">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>ext demo</title>

    <link rel="Stylesheet" type="text/css" href="resources/css/ext-all.css" />
    <link rel="Stylesheet" type="text/css" href="resources/css/xtheme-gray.css" />
    <script type="text/javascript" src="adapter/ext/ext-base.js"></script>
    <script type="text/javascript" src="ext-all.js"></script>
    <script type="text/javascript" src="src/locale/ext-lang-zh_CN.js"></script>
</head>
<body>
<script type="text/javascript">
    function ready()
    {
         Ext.Ajax.request
         ({
             url:"json.php",
             success: function(response,option)
             {
                 var resu = Ext.decode(response.responseText);
                 if(resu)
                 {
                     if(resu.success)
                     {
                        Ext.Msg.alert('提示消息',"加载成功！");
                     }
                     else
                     {
                        Ext.Msg.alert('提示消息',"加载失败！失败信息："+resu.error);
                     }
                 }
             },
             failure: function(response,option)
             {
                Ext.Msg.alert('提示消息',"加载失败！后台出现了严重的未捕获到的异常！");
             }
         });
    }
    Ext.onReady(ready);
</script>

</body>
</html>

后台处理页面json.php：

header('Content-Type: text/html; charset=utf-8');
  try{
      $hostname='localhost';
      $user='root123';
      $pwd='123';
      $dbname='uc';
      $sql='SELECT * FROM `uc_members`';
      $info=array();
      $connect = @mysql_connect($hostname,$user,$pwd);
      if ($connect === false)
      {
        throw new Exception('cannot connect do mysql');
      }
      $select = @mysql_select_db($dbname,$connect);
      if ($select === false)
      {
        throw new Exception('cannot select db');
      }
      $query = mysql_query($sql , $connect);
      if ($query === false)
      {
        throw new Exception('db syntax error');
      }
      $info['success'] = true;
      $info['error'] = 'all right';
      mysql_close($connect);
  }
  catch(Exception $ex)
  {
      $info['success'] = false;
      $info['error'] = $ex->getMessage();
  }

  $json_string=json_encode($info);
  echo $json_string;

效果图如下：