Hello,
I am trying to create a simple ajax chat using JQuery and ASP.NET. My code works like this:
- When the page loads it refreshes the 'chatbox' div with a request to the messages.aspx page, which handles getting new messages from the database and kicks off an auto refresh with the setTimeout().
- Whenever the user clicks the send button, it adds the message to the database inside the messages.aspx page_load code.
I am getting a stack overflow error right from the start when the timeout starts, and I am not sure what would cause this? Could it be caching? Maybe the code in messages.aspx can't complete running within those 5 seconds? Any help would be appreciated!
Also, I didn't worry about sql injection attacks yet b/c I was just trying to get it working with simple code.
Here's my code:
Client-side:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
<script src="jquery.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function() {
refreshChat();
$("#btnSend").click(function() {
addMessage();
});
return false;
});
function refreshChat()
{
$.get("messages.aspx", function(data) {
$("#chatbox").empty();
$("#chatbox").prepend(data);
});
setTimeout(refreshChat(), 5000);
}
function addMessage()
{
$.get("messages.aspx", {usr: $("#usr").val(), msg: $("#msg").val()} );
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div id="input">
username: <input type="text" name="usr" id="usr" /><br />
message:<br />
<textarea id="msg" name="msg" rows="5" cols="30"></textarea><br /><br />
<input type="button" id="btnSend" name="btnSend" value="Send" />
</div>
<div id="chatbox"></div>
</form>
</body>
</html>
Server Side:
using System;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.IO;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class messages : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
SqlConnection conn =
new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=F:\\Chatter\\App_Data\\messages.mdf;Integrated Security=True;User Instance=True");
conn.Open();
string sql;
SqlCommand comm;
if (Request["usr"] != null)
{
string user = Request["usr"].ToString();
string message = Request["msg"].ToString();
sql = "insert into messages (usr, msg, [date]) values ('"
+ user + "', '" + message + "', '" + DateTime.Now + "')";
comm = new SqlCommand(sql, conn);
comm.ExecuteNonQuery();
}
sql = "select top 5 usr, msg from messages order by [date] desc";
comm = new SqlCommand(sql, conn);
SqlDataReader dr = comm.ExecuteReader();
while (dr.Read())
{
Response.Write(dr["usr"].ToString() + ": <br/>" + dr["msg"] + "<br/><br/>");
}
dr.Close();
conn.Close();
}
}