simple ajax chat怎么用,json - Simple php ajax chat - Stack Overflow

i'm trying to do a simple php chat application that receives data from the client via ajax and writes that data to a text file for storage. But i keep getting anundefined index error on the lines where i try to get the 'name' and the 'message' after parsing the json.

this is the chat.php file:

if (isset($_POST['data']))

{

$data = $_POST['data'];

$chat = json_decode($data);

$name = $chat->name;

$msg = $chat->msg;

$file = "chat.txt";

$fh = fopen($file, 'w') or die("Sorry, could not open the file.");

if (fwrite($fh, $name + ":" + $msg))

{

$response = json_encode(array('exists' => true));

} else {

$response = json_encode(array('exists' => false));

}

fclose($fh);

echo ""

}

?>

this is the javascript:

$(document).ready(function() {

$("#btnPost").click(function() {

var msg = $("#chat-input").val();

if (msg.length == 0)

{

alert ("Enter a message first!");

return;

}

var name = $("#name-input").val();

var chat = $(".chat-box").html();

$(".chat-box").html(chat + "

" + msg + "

");

var data = {

Name : name,

Message : msg

};

$.ajax({

type: "POST",

url: "chat.php",

data: {

data: JSON.stringify(data)

},

dataType: "json",

success: function(response) {

// display chat data stored in text file

}

});

});

});