请问如何alert动态信息？

Question

if(!empty($msg)){
    echo "<script>";
    echo "    alert(".$msg.");";
    echo "</script>";
}
应该这样吧

Answer 1

<?php
$msg = "aaaaaaa\\n";
$msg .= "bbbbbbb\\n";
if(!empty($msg)){
    echo "<script>alert('".$msg."');</script>";
}
?>

Answer 2

if(!empty($msg)){
  $msg = preg_replace("[\r\n]+", "\\n", $msg);
  echo "<script>";
  echo "    alert('$msg');";
  echo "</script>";
}