PHP ILU INU IMU: Membuat Soal Random menggunakan SESSION

Teman2 ...mungkin sering dapat kode random.....
btw ini ada share sedikit ttg membuat soal random.....yang beda disini adalah sy menggunakan session sebagai alat perekam soal random, ybs....
keutungannya :
+SOAL BISA RANDOM
+SOAL MUNCUL SATU DEMI SATU
+MESKIPUN PENGGUNA BERPINDAH TAB BROWSER / REFRESH BERULANG TAPI SOAL TETAP STABIL

Nah itu .............

<?php

session_start();
$_SESSION["selesai"]=0;
if(!isset($_SESSION["ckat"])){
$kat=$_GET["kat"];
$_SESSION["chasil"]=0;
$_SESSION["crekap"]="";
$_SESSION["ckat"]=$kat;
$_SESSION["cawal"]="";
$sql="select * from `tb_soal` where matapelajaran='$kat'";
$jumsoal=getJum($conn,$sql);
$_SESSION["jumsoal"]=$jumsoal;
$_SESSION['student']=array();

$i=0;
$sqlc="select * from `$tbsoal` where matapelajaran='$kat' order by rand()";
$jumc=getJum($conn,$sqlc);
$arr=getData($conn,$sqlc);
foreach($arr as $d) {
$id_soal=$d["id_soal"];
$M[$i]=$id_soal;
//echo "$i=".$id_soal."<br>";
$i++;
}
$_SESSION["student"]=$M;
}
//-----------
for($i = 0 ; $i < count($_SESSION["student"]) ; $i++) {
//echo $i.'==='.$_SESSION["student"][$i].'<br>';
}

if(!isset($_SESSION["m"])){
$_SESSION["m"]=0;
}

if(isset($_GET["Pilih"])){
$kat=$_SESSION["ckat"];
$sql="select * from `tb_soal` where matapelajaran='$kat'";
$jumsoal=getJum($conn,$sql);

$x=$_SESSION["m"];
if($x==0){
$_SESSION["cawal"]=WKT(date("Y-m-d"))." ". date("H:i:s");
}
$id_soal=$_SESSION["student"][$x];
$_SESSION["m"]++;
//jawaban=A&id_soal=27&jawab_benar=B&Pilih=Pilih&mnu=soal
$jawaban=$_GET["jawaban"];
$id_soal=$_GET["id_soal"];
$jawab_benar=$_GET["jawab_benar"];
$hasil="Salah";
if($jawab_benar==$jawaban){
$hasil="Benar";$_SESSION["chasil"]=$_SESSION["chasil"]+1;
$_SESSION["crekap"].="Soal ".$_SESSION["m"]." (ID:$id_soal):Benar,";
}
else{
$_SESSION["crekap"].="Soal ".$_SESSION["m"]." (ID:$id_soal):Salah,";
}

if($_SESSION["m"]>=($jumsoal)){
//if($_SESSION["m"]>=99){//artinya dari 1000soal hanya 100 yg ditampilkan
$ahir=WKT(date("Y-m-d"))." ". date("H:i:s");
$waktu="Jumlah Soal: ".$_SESSION["jumsoal"].", Waktu Pengerjaan: ".$_SESSION["cawal"]." s/d ".$ahir." WIB";
$sql="INSERT INTO `tb_hasil` (`id`, `kode_user`, `id_soal`, `rekapitulasi`, `hasil`, `keterangan`)
VALUES ('', '".$_SESSION["cid"]."', '".$_SESSION["ckat"]."', '".$_SESSION["crekap"]."', '".$_SESSION["chasil"]."', '$waktu')";
$simpan=process($conn,$sql);

$_SESSION["selesai"]=1;
}
}

if($_SESSION["selesai"]==1){
unset($_SESSION["selesai"]);
unset($_SESSION["m"]);
unset($_SESSION["student"]);
unset($_SESSION["crekap"]);
unset($_SESSION["chasil"]);
unset($_SESSION["jumsoal"]);
$_SESSION["student"]=array();

unset($_SESSION["student"]);
unset($_SESSION["m"]);
unset($_SESSION["ckat"]);
session_destroy();
echo "<script>alert('terimakasih atas partisipasinya.......See You Later...');
document.location.href='index.php';</script>";
}
else{

$m=$_SESSION["m"];
$id_soal=$_SESSION["student"][$m];
//echo"M=$m==$id_soal<br>";
$no=$m+1;

$sql="select * from `tb_soal` where id_soal='$id_soal'";
$d=getField($conn,$sql);
$id_soal=$d["id_soal"];
$mata_pelajaran=$d["mata_pelajaran"];
$soal=$d["soal"];
$jawab_a=$d["jawab_a"];
$jawab_b=$d["jawab_b"];
$jawab_c=$d["jawab_c"];
$jawab_d=$d["jawab_d"];
$jawab_benar=$d["jawab_benar"];
$gambar=$d["gambar"];

$kat=$_SESSION["ckat"];
?>

<form name='form1' method='get' action=''>
<table width='100%' border='0'>
<tr>
<td colspan='4'> </td>
</tr>
<tr>
<td width='23%' rowspan='3' align='center' valign='middle'>
<a href='#' onclick='buka(\"soal/zoom.php?id=$id_soal\")'><img src='graduation.jpg' width='150' height='180' /></a>
</td>
<td colspan='3'><h1><?php echo $no.". ".$soal;?> </h1><hr></td>
</tr>

<tr>
<td colspan="3"><font size="+2">
<input type="radio" id="pil" name="jawaban" value="A">A. <?php echo $jawab_a;?><br>
<input type="radio" id="pil" name="jawaban" value="B">B. <?php echo $jawab_b;?><br>
<input type="radio" id="pil" name="jawaban" value="C">C. <?php echo $jawab_c;?><br>
<input type="radio" id="pil" name="jawaban" value="D">D. <?php echo $jawab_d;?><br>
<input type="hidden" id="id_soal" name="id_soal" value="<?php echo $id_soal;?>"><br />
<input type="hidden" id="jawab_benar" name="jawab_benar" value="<?php echo $jawab_benar;?>">

</font><br /><br /><br />
<input type="submit" value="Pilih" name="Pilih">
<input type="hidden" value="soal" name="mnu">
<input type="hidden" value="<?php echo $kat;?>" name="kat">
</td>
</tr>
<tr>
<td width="20%"> </td>
<td width="28%"> </td>
<td width="29%" colspan='2'> </td>
</tr>
</table>
</form>

<?php
}
?>

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