如何修复帖子通过java发送％ad和php接收？

Question

O have page with some javascript code and I sending data from textarea to php file save.php to save data on server

code:

var data = 'data='+document.getElementById("data").value;
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange=function(){
  if (xmlhttp.readyState==4 && xmlhttp.status==200){
    response.innerHTML=xmlhttp.responseText;
  }
}
xmlhttp.open("POST","save.php",true);
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.send(data);

send data is okey but if I echo data in php on save.php it's broken %ad -> �

save.php code:

$post_data = $_POST['data'];
echo $post_data;

textarea contains:

somethink like:

%packages --excludedocs
@^minimal
@core
kexec-tools
%end

%addon com_redhat_kdump --enable --reserve-mb='auto'
%end

with %addon is problem becouse it changed to �don com_redhat_kdump.....

Answer 1

That � is a special character which means an invalid character code was used. This is a sign that you have used an invalid encoding.

I would suggest you set the character encoding of your request in javascript.

xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded;charset=utf-8");

Also don't echo the data directly into a web page from php without encoding it in HTML.

echo htmlentities($post_data, ENT_HTML5, 'UTF-8');

You can also look at the web request headers using your browsers development tools to verify that the server isn't sending the web page using a different character encoding. If it is you can set the header in PHP.

header('Content-Type: text/html; charset=utf-8');