我无法用PHP更新MySQL数据库

Question

I am trying to update the mysql database using PHP but somehow I am not able to do the same. It echos the message that it is successfully updated but it doesn't update it. Please help. Please check the code and tell me the correction: First I am showing the form then the PHP code

<?php
$id=$_GET['id'];
$sql="select * from members_data where id='$id'";
$data=mysql_query($sql);
$row=mysql_fetch_array($data);
?>

<form method="post" action="edit1.php" name="form1" enctype="multipart/form-data">
<table  width="400" align="left">
<tr>
<td style="width:300px;">
Name
</td>
<td><input placeholder="What's the latest news?" type="text" name="name" style="height:20px;      width:300px;" value="<?php echo $row['name']?>" /></td>
</tr>
<tr>
<td style="width:300px;">
Family Image
</td>

<td width="69%" height="25"><input type="file" name="file" style="height:20px; width:300px;" /></td>
</tr>
<tr>
<td style="width:300px;">
Membership No.
</td>
<td><input placeholder="What's your membership number?" type="text" name="membership_no" style="height:20px; width:300px;" value="<?php echo $row['membership_no']?>" /></td>
</tr>
<tr>
<td style="width:300px;">
Address
</td>
<td><input placeholder="What's the latest news?" type="text" name="address" style="height:20px; width:300px;" value="<?php echo $row['address']?>" /></td>
</tr>
<tr>
<td style="width:300px;">
Contact Number
</td>
<td><input placeholder="What's the latest news?" type="text" name="contact_no" style="height:20px; width:300px;" value="<?php echo $row['contact_no']?>" /></td>
</tr>

<tr>
<td>
<input type="hidden" name="id" value="<?php echo $res['id']?>" />
</td>
<td style="text-align:right; width:300px;"><input type="submit" name="edit1" value="Update" /></td>
</tr>
</table>
</form>

Now starts the php code:

<?php
include("conn.php");
?>
<?php


if(isset($_POST['edit1']))
{
$allowedExts = array("gif", "jpeg", "jpg", "png", "pdf", "doc", "docx");
$extension = end(explode(".", $_FILES["file"]["name"]));
if ((($_FILES["file"]["type"] == "image/gif")
|| ($_FILES["file"]["type"] == "image/jpeg")
|| ($_FILES["file"]["type"] == "application/msword")
|| ($_FILES["file"]["type"] == "application/pdf")
|| ($_FILES["file"]["type"] == "application/vnd.openxmlformats-officedocument.wordprocessingml.document")
|| ($_FILES["file"]["type"] == "text/plain")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/pjpeg")
|| ($_FILES["file"]["type"] == "image/x-png")
|| ($_FILES["file"]["type"] == "image/png"))
&& in_array($extension, $allowedExts))
  {
  if ($_FILES["file"]["error"] > 0)
    {
    //echo "Return Code: " . $_FILES["file"]["error"] . "<br />";
    }
  else
    {
    //echo "Upload: " . $_FILES["file"]["name"] . "<br />";
    //echo "Type: " . $_FILES["file"]["type"] . "<br />";
    //echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />";
    //echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br />";

    if (file_exists("images/family_pics/" . $_FILES["file"]["name"]))
      {
      //echo $_FILES["file"]["name"] . " already exists. ";
      }
    else
      {
      move_uploaded_file($_FILES["file"]["tmp_name"],
      "images/family_pics/" . $_FILES["file"]["name"]);
      //echo "Stored in: " . "images/" . $_FILES["file"]["name"];
      }
    }
  }
else
  {
  //echo "Invalid file";
  }
$id=$_POST['id'];
$name=$_POST['name'];
$image=$_FILES["file"]["name"];
$membership_no=$_POST['membership_no'];
$address=$_POST['address'];
$contact_no=$_POST['contact_no'];

$query=mysql_query("update members_data set name='$name',family_image='$image',membership_no='$membership_no',address='$address',contact_no='$contact_no' WHERE id='$id'")  or die(mysql_error());

// if successfully updated. 
if($query){
echo "Successful";
echo "<BR>";
echo "<a href='admin_detail.php'>View result</a>";
}

else {
echo "ERROR";
}

}

?>
<?php /*?><script type="text/javascript">window.location="edit_records.php"</script><?php */?>

Answer 1

The likely problem is with line:

<input type="hidden" name="id" value="<?php echo $res['id']?>" />

I didn't see $res defined anywhere.

You probably want:

<input type="hidden" name="id" value="<?php echo $row['id']?>" />

Also I recommend studying this: How can I prevent SQL injection in PHP?