无法识别文件目录路径的变量

Question

so far I've successfully moved an uploaded image to its designated directory and stored the file path of the moved image into a database I have.

Problem is, however, is that the img src I have echoed fails to read the variable containing the file path of the image. I've been spending time verifying the validity of my variables, the code syntax in echoing the img src, and the successful execution of the move/storing code, but I still get <img src='' when I refer to the view source of the page that is supposed to display the file path contained in the variable.

I believe the file path is stored within the variable because the variable was able to be recognized by the functions that both moved the image to a directory and the query to database.

My coding and troubleshooting experience is still very adolescent, thus pardon me if the nature of my question is bothersomely trivial.

Before asking this question, I've searched for questions within SOF but none of the answers directly addressed my issue (of the questions I've searched at least).

Main PHP Block

  //assigning post values to simple variables
        $location = $_POST['avatar'];
                    .
                    .
                    .

  //re-new session variables to show most recent entries
        $_SESSION["avatar"] = $location;
                    .
                    .
                    .

  if (is_uploaded_file($_FILES["avatar"]["tmp_name"])) {

        //define variables relevant to image uploading
             $type = explode('.', $_FILES["avatar"]["name"]);
             $type = $type[count($type)-1];
             $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
             $rdn = substr(str_shuffle($chars), 0, 15);
        //check image size
             if($_FILES["avatar"]["size"] > 6500000) {
               echo"Image must be below 6.5 MB.";
               unlink($_FILES["avatar"]["tmp_name"]);
               exit();
             }
       //if image passes size check continue
             else {
               $location = "user_data/user_avatars/$rdn/".uniqid(rand()).'.'.$type;
               mkdir("user_data/user_avatars/$rdn/");
               move_uploaded_file( $_FILES["avatar"]["tmp_name"], $location);
           }

           }
           else {
             $location = "img/default_pic.jpg";
           }

HTML Block

              <div class="profileImage">
                <?php

                  echo "<img src='".$location."' class='profilePic' id='profilePic'/>";

                ?><br />
                  <input type="file" name="avatar" id="avatar" accept=".jpg,.png,.jpeg"/>
                    .
                    .
                    .

View Source

<div class="profileImage">
                <img src='' class='profilePic' id='profilePic'/><br />
                  <input type="file" name="avatar" id="avatar" accept=".jpg,.png,.jpeg"/>
                    .
                    .
                    .

Answer 1

Alright, I've finally found the error and was able to successfully solve it!

Simply declare a avatar session variable to the $location variable after updating the table, update the html insert by replacing all $location variables with $_SESSION["avatar_column"] and you are set!

PHP:

    $updateCD = "UPDATE users SET languages=?, interests=?, hobbies=?, bio=?, personal_link=?, country=?, avatar=? WHERE email=?";
  $updateST = $con->prepare($updateCD);
  $updateST->bind_param('ssssssss', $lg, $it, $hb, $bio, $pl, $ct, $location, $_SESSION["email_login"]);
  $updateST->execute();

  $_SESSION["avatar"] = $location;   //Important!

  if ($updateST->errno) {
      echo "FAILURE!!! " . $updateST->error;
      }

HTML:

    <div class="profileImage">
                <?php
                $_SESSION["avatar"] = (empty($_SESSION["avatar"])) ? "img/default_pic.jpg" : $_SESSION["avatar"] ;
                 echo "<img src='".$_SESSION["avatar"]."' class= 'profilePic' id='profilePic'> ";
                 ?>
        .
        .
        .

Thank you!