send data with ajax when pressing enter

Question

i have a form like this :

Answer 1

Move out SendData from document.ready

function SendData() {
        $.ajax({
            url: "save.php",
            type: "post",
            data: "msg="+$('#chat_in').val(),
            dataType: 'json', 
            success: function(){   
                alert("Sent");
            },
            error:function(){
                alert("failure");                
            }
        });
    }

$(document).ready(function () {

    $('#chat_in').keypress(function(e) {
        if(e.which == 13) {
            alert('You pressed enter!');
            SendData();
        }
    });

    $('#bt').click(function() {
        SendData();
    });
});