Brief description of php query database to return json data
This article mainly introduces the simple implementation of PHP to query the database and return json data, and attaches 2 sample codes. It is very simple and practical. Friends in need can refer to it.
Sample code one:
// 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);
Sample code two:
<?php //需要执行的SQL语句 //单条 $sql="select id,name from tbl_user where id=1"; //多条数据 //$sql="select id,name from tbl_user"; //调用conn.php文件进行数据库操作 require('Conn.php'); //提示操作成功信息,注意:$result存在于conn.php文件中,被调用出来 if($result) { // $array=mysql_fetch_array($result,MYSQL_ASSOC); /*数据集 $users=array(); $i=0; while($row=mysql_fetch_array($result,MYSQL_ASSOC)){ echo $row['id'].'-----------'.$row['name'].'</br>'; $users[$i]=$row; $i++; } echo json_encode(array('dataList'=>$users)); */ /*单条数据*/ $row=mysql_fetch_row($result,MYSQL_ASSOC); echo json_encode(array('jsonObj'=>$row)); } mysql_free_result($result); //释放结果 mysql_close(); //关闭连接 ?>
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