PHP upload files no request

Question

<?php
　if ($_FILES["public_html"]["error"] > 0){
　　echo "Error: " . $_FILES["file"]["error"];
　}else{
　　echo "File name: " . $_FILES["file"]["name"]."<br/>";
　　echo "File type: " . $_FILES["file"]["type"]."<br/>";
　　echo "File size: " . ($_FILES["file"]["size"] / 1024)." Kb<br />";
　　 move_uploaded_file($_FILES["file"]["tmp_name"],"public_html/".$_FILES["file"]["name"]);　
　}
?>
when I try to upload file with this PHP and the browser showed that currently unable to handle this request. HTTP ERROR 500.

Answer 1

I use web host app instead of local server.