php 查询数据库返回json数据

// 设置返回json格式数据
header('content-type:application/json;charset=utf8');

//连接数据库
$link = mysql_connect("localhost", "root", "root") or die("Unable to connect to the MySQL!");

mysql_query("SET NAMES 'UTF8'");

mysql_select_db("jilinwula", $link) or die("Unable to connect to the MySQL!");

// 获取分页参数
$page = 0 ;
$pageSize = 3;

if(!is_null($_GET["page"])) {
$page = $_GET["page"];
}

if(!is_null($_GET["pageSize"])) {
$pageSize = $_GET["pageSize"];
}

// 查询数据到数组中
$result = mysql_query("select username,password from userinfo limit " . $page . ", ". $pageSize ."");

$results = array();
while ($row = mysql_fetch_assoc($result)) {
$results[] = $row;
}

// 将数组转成json格式
echo json_encode($results);

// 关闭连接
mysql_free_result($result);

mysql_close($link);