php构造json数组与对象

<?php
/**
* @Author: feitian
* @Date:   2017-08-14 16:49:41
* @Last Modified by:   feitian
* @Last Modified time: 2017-08-14 16:50:14
*/

//1.导入配置文件
require("./conf/dbconfig.php");
$link = mysql_connect(HOST, USER, PASS);
mysql_select_db(DBNAME);

$page = $_GET["curPage"] ? $_GET["curPage"] : 1;

$num = 10;
$ofset = ($page - 1) * $num;

$t_sql = "SELECT student_name,course_name,mobile FROM edu_trxorder WHERE course_id=898 AND trx_status='SUCCESS'";

$t_res = mysql_query($t_sql);

//总记录数
$total = mysql_num_rows($t_res);

//总页数
$totalpage = ceil($total / $num);

$sql = "SELECT student_name,course_name,mobile FROM edu_trxorder WHERE course_id=898 AND trx_status='SUCCESS' LIMIT $ofset,$num ";

$res = mysql_query($sql);

$arr = array();

/*
while ($row = mysql_fetch_assoc($res)) {
$arr[] = $row;
}*/

$sub = [];

$sub[] = ["xq1"=>"星期一","xq2"=>"星期二","xq3"=>"星期三"];

while ($row = mysql_fetch_assoc($res)) {

$arr[] = ["student_name" => $row["student_name"], "course_name" => $row["course_name"], "mobile" => $row["mobile"], "sub" => $sub];

}

$a = array("curPage" => $page, "totalCount" => $total, "totalpage" => $totalpage, "data" => $arr, "sql" => "$sql");

//echo json_encode($a);

echo json_encode($arr);