How to upload a file in php with php validation of extension?

Simply copy and paste this code on your page
And your input file name will be uploadedfile
Like <input type="file" name="uploadedfile" />

and on submit of this page you will add this code
$youruniqueid could be anything like userid or projected
on the basis of this it will create folder for image upload


$projId=$youruniqueid;
   if(!empty($_FILES['uploadedfile']['name'])){
    $imgExtension = array("jpg","jpe","jpeg","gif","png","GIF","JPG","JPEG","txt","pdf","PDF","docx","xlsx","pptx","pptm","doc","dot","xls","ppt");
   
    $image_name = pathinfo($_FILES['uploadedfile']['name']);
    $extension = strtolower($image_name['extension']);
   
    if(in_array($extension,$imgExtension)){
   
  
     $file_name = $_FILES['uploadedfile']['name'];
     $ext = end(explode('.',$file_name));
  
    
     if ($_SERVER['HTTP_HOST'] == 'localhost')
     $folder_path = 'files/project_attachment/'.$projId; // Relative to the root
    
    else
     $folder_path = '/files/project_attachment/'.$projId; // Relative to the root
    
     $save_path  = $folder_path.'/'.md5(date('ymdhis')).'.'.$ext;
    
// for create a new folder like  /files/project_attachment/554/
if(!is_dir($folder_path)){
     mkdir($folder_path, 0777, TRUE);
     chmod($folder_path , 0777);
     }
    
    
                 if(move_uploaded_file($_FILES['uploadedfile']['tmp_name'] , $save_path))
                {
                     echo "upload successfully";
                }
     }
     else
     {
      echo "Please upload suitable attachment";
     }
   }