PHP - 通过QueryString循环

Question

Trying to loop through a querystring in php but only getting last value. What should I be doing to get all values?

example: querystring = ?style=ranch&style=barn&style=colonial

php:

$sqlStyle = "SELECT DISTINCT COUNT(*) as count  FROM houses_single ";
$i = 1;
foreach ($_GET as $key => $value) {
    if ($i == 1){
        $sqlStyle .= "where ";
     }else{
        $sqlStyle .= " and ";
    }
    $sqlStyle .=  $key . " like '%" . $value ."%'";
    $i++;
 }
 echo $sqlStyle;

Result: SELECT DISTINCT COUNT(*) as count FROM houses_single Where Houses like '%colonial%'

Answer 1

The query parameter "style" is an array in this case and must be identified by square brackets - if not, the last key=value pair will overwrite the others.

?style[]=ranch&style[]=barn&style[]=colonial

$_GET['style'] is an array then you can loop over by using foreach:

foreach ($_GET['style'] as $value) {
    // ...
}

if 'style' is not the only parameter you want to add, you can use a is_array() check in the foreach loop:

    foreach ($_GET as $key => $value) {
        if ($i == 1){
            $sqlStyle .= "where ";
         }else{
            $sqlStyle .= " and ";
         }

         if(is_array($value)) {
             $sec = array();
             foreach($value as $second_level) {
                 $sec[] =  $key . " LIKE '%" . $second_level."%'";
             }
             $sqlStyle .= implode(' AND ', $sec);
         }
         else {
            $sqlStyle .=  $key . " LIKE '%" . $value ."%'";
         }

         $i++;
     }
     echo $sqlStyle;

alternative without foreach:

<?php

$statement = "SELECT DISTINCT COUNT(*) as count FROM `houses_single`";

if(is_array($_GET)) {
   $statement .= ' WHERE';

   // create copy to keep the $_GET array
   $add_where = $_GET;

   array_walk(function($elem,$key){
      is_array($elem) {
         return implode(' AND ', array_map(function($sec) using ($key)  {
             return "$key LIKE '%$sec%'";
         }, $elem);
      }
      else {
            return "$key LIKE '%$elem%'";
      }
   },$add_where);

   $statement .= implode(' AND ', $add_where);
}

(codes are untested)

Sidenode about safety: I hope you won't use this code snippet you provided in productive environment without any escaping of the parameters.