PHP 提取数据库数据并转化为二维 json 的方法

首先贴一段示例代码:

<?php
include "con_db.php";//连接数据库
$sql="select * from note order by note_date desc limit ".($index*10).",10"; //sql语句
	$result=mysql_query($sql);//获得结果
$note;$i=0; //初始化变量
while($infor=mysql_fetch_array($result))
	{
 //把结果放到一个一维数组里
	$note["id"]=$infor['note_id'];
  	$note["content"]=$infor['note_content'];
 $note["date"]=$infor['note_date'];
 $note["username"]=$infor['username'];
 //放到二维数组里
 $notes[$i++]=$note;
	}
 echo json_encode($notes );
?>

[{"id":"12","content":"u662f","date":"2014-05-24 09:31:52","username":"u532f"},
{"id":"31","content":"u642f","date":"2014-05-24 09:31:49","username":"u322f"},
{"id":"70","content":"u692f","date":"2014-05-24 09:31:48","username":"u132f"}]

<?php
	$h =urlencode("开心");
	echo $h;
	$x =urldecode($h);
	echo $x;
?>

%BF%AA%D0%C4开心

<?php
while($infor=mysql_fetch_array($re))
	{
	$note["id"]=$infor['note_id'];//数字不需要编码
  	$note["content"]=urlencode($infor['note_content']);//汉字需要编码
 $note["date"]=$infor['note_date'];
 $note["username"]=urlencode($infor['username']);
 $notes[$i++]=$note;
	}
 echo urldecode(json_encode($notes ));//转化成json之后再用urldecode解码为汉字
?>

[{"id":"22","content":"文章","date":"2014-05-24 09:31:52","username":"王"},
{"id":"21","content":"内容","date":"2014-05-24 09:31:49","username":"李"},
{"id":"20","content":"可以","date":"2014-05-24 09:31:48","username":"冯"}]