This article mainly shares with you how to query data using PHP to connect to the database, mainly using code methods. I hope it can help everyone.
header("Access-Control-Allow-Origin: *"); header("Control-type:application/json;charset='utf-8'"); $con = mysql_connect('url','username','pwd'); $mysql_db = mysql_select_db('npi',$con) or die ('连接失败'.mysql_errno); mysql_query("set names 'uft8'"); $sql = "select lineno from lineno6s"; $query = mysql_query($sql); if($query&&mysql_num_rows($query)){ while ($row = mysql_fetch_assoc($query)) { $data [] = $row; } } else if(mysql_num_rows($query)==null){ $data = '{content:"blank"}'; echo $data; return; } $jsondata = json_encode($data,JSON_UNESCAPED_UNICODE); echo $jsondata; mysql_close(); exit();
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