$_POST method turns empty - php

Question

Firstable, hello everyone. I have issue about the $_POST method, when I write this code block;
if (isset($_POST['menuduzenle'])) {
$menu_id=$_POST['menu_id']; //It didn't turn with value in mysql
$ayarguncelle=mysql_query("update menuler set menu_ad='".$_POST['menu_ad']."',menu_link='".$_POST['menu_link']."'where menu_id='$menu_id'");
if(mysql_affected_rows())
{
header("Location:../menuleriduzenle.php?guncelleme=basarili&menu_id=$menu_id");
}else{
header("Location:../menuleriduzenle.php?guncelleme=basarisiz&menu_id=$menu_id");}
}
menu_id turns emty, what I need to do for solve this?
and here it's html code
form
<form action="network/islem.php" method="POST">
<div class="col-md-12">
<div class="form-group col-md-9">
<label>Menu Adı: </label>
<input class="form-control" name="menu_ad" value="<?php echo $menucek['menu_ad']; ?>" />
</div>
</div>
<div class="col-md-12">
<div class="form-group col-md-9">
<label>Menu Link: </label>
<input class="form-control" name="menu_link" value="<?php echo $menucek['menu_link']; ?>" />
</div>
</div>
<div class="col-md-12">
<div class="form-group col-md-6">
<input class="btn btn-primary col-md-3" type="submit" name="menuduzenle" value="Edit Menu">
</div>
</form>
and
<td><button class="btn btn-primary col-md-12">Edit</button></td>

Answer 1

You not send any one input with name 'menu_id' on your from.
<form action="network/islem.php" method="POST">
<div class="col-md-12">
<div class="form-group col-md-9">
<label>Menu Adı: </label>
<input class="form-control" name="menu_ad" value="<?php echo $menucek['menu_ad']; ?>" />
</div>
</div>
<div class="col-md-12">
<div class="form-group col-md-9">
<label>Menu Link: </label>
<input class="form-control" name="menu_link" value="<?php echo $menucek['menu_link']; ?>" />
</div>
</div>
<div class="col-md-12">
<div class="form-group col-md-6">
<input class="btn btn-primary col-md-3" type="submit" name="menuduzenle" value="Edit Menu">
</div>
<input type="hidden" name="menu_id" value="<?php echo $_GET['menu_id'] ?>" />
</form>
You input name "menu_ad" would be "menu_id" or fault other input with name "menu_id" on you sample.