PHP 5 - 警告：非法字符串偏移[重复]

Question

This question already has an answer here:

• Illegal string offset Warning PHP 14 answers
• Reference - What does this error mean in PHP? 34 answers

i have a problem with illegal string offset

how to fixed this problem, so many way i'm trying but it's not solved.

this's my code:

<?php
  include "config/koneksi.php"; 
  $dlpenyakit = $_POST['Gejala'];
  echo json_encode($dlpenyakit);

  foreach($dlpenyakit as $ddata){
  $sql   = "SELECT * FROM rule where idGejala=$ddata";
     $diagnosaa = mysql_query($sql) or exit("Error query: <b>".$sql."</b>.");
      foreach(mysql_fetch_assoc($diagnosaa) as $data2)
      {
          $rl = $data2['idPenyakit'];
          $sql = "SELECT * FROM rule where idPenyakit=$rl";
          $rulee = mysql_query($sql) or exit("Error query: <b>".$sql."</b>.");
          $jml_prob = 1;
           foreach (mysql_fetch_assoc($rulee) as $data4)
           {
               $probb = $data4['Probabilitas_gejala'];
               echo $probb;
        // perkalian prob gejala
        $jml_prob = $jml_prob*$probb;
        echo ' = '.$jml_prob;
        echo "<br>";
           }
     ?>

thank you

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