PHP function get array returned by second function

Question

I have 2 functions (Located in same file)

f1 = getBlogCommentList

f2 = getBlogReplyList

I want function f1 to call f2 $this->getBlogReplyList($post_id,$comment['id']);, f2 function collect data from sql based on f1 sent parameters and returns array with data return $blog_replies;. And returned data I want to use in f1, but can't understand how to reach this returned data. foreach ($blog_replies as $reply) { //Do stuff with returned data }

Notice: Undefined variable: blog_replies in D:\xampp\htdocs\models\BlogModel.php on line 146

Warning: Invalid argument supplied for foreach() in D:\xampp\htdocs\models\BlogModel.php on line 146

In Line 146 I have foreach($blog_replies as $replies)

f1 function (getBlogCommentList)

public function getBlogCommentList($post_id){
try{

    $sortby = "bla bla bla";

    $stmt = $this->conn->prepare("$sortby");
    $stmt->execute();
    $result = $stmt->fetchAll();

    $blog_comments = array();

    foreach($result as $comment){
        $blog_comments[] = $comment;
        $this->getBlogReplyList($post_id,$comment['id']);
    }

    foreach ($blog_replies as $reply) {
        //Do stuff with returned data
    }

    return $blog_comments;

  }
  catch(PDOException $e)
  {
    echo $e->getMessage();
  }
}

f2 function (getBlogReplyLyst)

public function getBlogReplyList($post_id,$comment_id){
try{

    $sortby = "bla bla bla";

    $stmt = $this->conn->prepare("$sortby");
    $stmt->execute();
    $result = $stmt->fetchAll();

    $blog_replies = array();

    foreach($result as $post){
        $blog_replies[] = $post;
    }

    return $blog_replies;

  }
  catch(PDOException $e)
  {
    echo $e->getMessage();
  }
}

Answer 1

You need to assign the output of the called function to a variable, because the variables are only accessible within your function, i.e.:

$blog_replies = $this->getBlogReplyList($post_id,$comment['id']);

foreach ($blog_replies as $reply) {
    //Do stuff with returned data
}

You could also consider using class variables, this way you can access the variable in each function of your object. Note the usage of $this->blog_relies, the variable definition at the top and the removal of the return statement

Example:

class ExampleClass {

  private $blog_replies;

  public function getBlogReplyList($post_id,$comment_id){
    try{

        $sortby = "bla bla bla";

        $stmt = $this->conn->prepare("$sortby");
        $stmt->execute();
        $result = $stmt->fetchAll();

        $this->blog_replies = array();

        foreach($result as $post){
            $this->blog_replies[] = $post;
        }

        // The return is now obsolete
        // return $blog_replies;

      }
      catch(PDOException $e)
      {
        echo $e->getMessage();
      }
   }

  public function getBlogCommentList($post_id){
    try{

      $sortby = "bla bla bla";

      $stmt = $this->conn->prepare("$sortby");
      $stmt->execute();
      $result = $stmt->fetchAll();

      $blog_comments = array();

      foreach($result as $comment){
        $blog_comments[] = $comment;
        $this->getBlogReplyList($post_id,$comment['id']);
      }

      foreach ($this->blog_replies as $reply) {
        //Do stuff with returned data
      }

      return $blog_comments;

    }
    catch(PDOException $e)
    {
      echo $e->getMessage();
    }
  }


}

Answer 2

Modify f1 as follows:

public function getBlogCommentList($post_id){
    try{

        $sortby = "bla bla bla";

        $stmt = $this->conn->prepare("$sortby");
        $stmt->execute();
        $result = $stmt->fetchAll();

        $blog_comments = array();

        foreach($result as $comment){
            $blog_comments[] = $comment;

            $blog_replies = $this->getBlogReplyList($post_id,$comment['id']);
            foreach ($blog_replies as $reply) {
                //Do stuff with returned data
            }
        }

        return $blog_comments;

    }
    catch(PDOException $e)
    {
        echo $e->getMessage();
    }
}