标题CORS“Access-Control-Allow-Origin”缺少Codeigniter

Question

I'm trying to learn how to use Ajax in Codeigniter . This is why I tried to make a small view and a test controller but does not seem to work. Can you help me? This is my view:

    <script src="https://code.jquery.com/jquery-3.0.0.min.js" integrity="sha256-JmvOoLtYsmqlsWxa7mDSLMwa6dZ9rrIdtrrVYRnDRH0=" crossorigin="anonymous"></script>
<form name="modulo">
    <p>Nome</p>
    <p><input type="text" name="nome" id="nome"=></p>
    <p>Cognome</p>
    <p><input type="text" name="cognome" id="cognome"></p>
    <input type="button" id="bottone" value="Invia i dati">
</form>
<div id="risultato"></div>
<script type="text/javascript">
$(document).ready(function() {
  $("#bottone").click(function(){
    var nome = $("#nome").val();
    var cognome = $("#cognome").val();
    $.ajax({
      type: "POST",
      url: "http://lifedesktop/welcome/ajax",
      data: "nome=" + nome + "&cognome=" + cognome,
            crossOrigin: true,
      dataType: "html",
      success: function(msg)
      {
        $("#risultato").html(msg);
      },
      error: function()
      {
        alert("Don't work...");
      }
    });
  });
});
</script>

And this is my controller:

public function ajax()
    {
        if($this->input->is_ajax_request()){
        $nome = $_POST["nome"];
        $cognome = $_POST["cognome"];
        if ($nome == "" || $cognome == "")
        {
                echo "Inserire nome e cognome!";
        }
        else
        {
                echo $nome . " " . $cognome;
        }
        }
    }

In the console web i have this error:

header CORS “Access-Control-Allow-Origin” missing.

Can you help me?

Answer 1

If you have access to the api, so set this header to your php code:

header('Access-Control-Allow-Origin: *');  

If not, you can only use that api in your own web page, by installing some CORS plugins for chrome or firefox like this. (It's not possible to share this with users)