I have written a program in which i am reading data from Serial Port. After Reading the data, i am Displaying the status of it in a textbox named "lblStatus". But after reading from the port everytime, the text in the textbox is not getting updated.
Here is my aspx file code.
<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="true" CodeFile="AddRFID.aspx.cs" Inherits="AddRFID" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<div id="wrapper">
<div class="row">
<div class="col-lg-12">
<h1 class="page-header">Add RFID</h1>
</div>
</div>
<div class="row">
<div class="col-lg-12">
<div class="panel panel-default">
<div class="panel-heading">
Add RFID
</div>
<div class="panel-body">
<div class="row">
<div class="col-lg-6">
<div class="panel-body">
<form id="Form1" runat="server">
<asp:Button ID="btnStart" runat="server" Text="Start" OnClick="btnStart_Click"/>
<asp:Panel ID="Panel1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<asp:UpdatePanel ChildrenAsTriggers="false" OnPreRender="UpdatePanel1_PreRender" UpdateMode="Conditional" ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:TextBox ID="txtStatus" CssClass="form-control" runat="server" Rows="20" Height="200px" ></asp:TextBox>
</ContentTemplate>
</asp:UpdatePanel>
<asp:Button ID="Button2" runat="server" Text="Read" OnClick="Button2_Click" />
</asp:Panel>
</form>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</asp:Content>
Here is my .cs file for it.
public partial class AddRFID : System.Web.UI.Page
{
RFIDImplementation ri;
public string rfid_no;
public SerialPort port;
public static string withoutLast, result;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Panel1.Visible = false;
txtStatus.TextMode = TextBoxMode.MultiLine;
}
}
protected void submit_Click(object sender, EventArgs e)
{
}
protected void btnStart_Click(object sender, EventArgs e)
{
Panel1.Visible = true;
port = new SerialPort("COM4", 9600, Parity.None, 8, StopBits.One);
SerialPortProgram();
}
private void SerialPortProgram()
{
Console.WriteLine("Incoming Data:");
// Attach a method to be called when there
// is data waiting in the port's buffer
port.DataReceived += new
SerialDataReceivedEventHandler(port_DataReceived);
// Begin communications
try
{
port.Open();
result += "Port Open \n";
}
catch (UnauthorizedAccessException uae)
{
result += "Access Denied to Port \n";
}
catch (InvalidOperationException ioe)
{
result += "Port Already Open \n";
}
catch (IOException io)
{
result += "RFID not Attached \n";
}
}
private void port_DataReceived(object sender,
SerialDataReceivedEventArgs e)
{
// Show all the incoming data in the port's buffer
string s = port.ReadLine();
withoutLast = s.Substring(0, s.Length - 4);
ShowData(withoutLast);
}
private void ShowData(String withoutLast)
{
RFIDLogic rl = new RFIDLogic();
RFID r = new RFID();
r.R_No = withoutLast;
r.O_ID = Convert.ToInt32(null);
r.R_Status = false;
if (rl.CheckExistingRno(r) == 0)
{
rl.Insert(r);
result = result + "RFID Added \n";
}
else
{
result = result + "RFID Already Exist \n";
}
}
protected void UpdatePanel1_PreRender(object sender, EventArgs e)
{
txtStatus.Text = result;
}
protected void UpdatePanel1_Load(object sender, EventArgs e)
{
txtStatus.Text = result;
}
}
After the appropriate operation I am appending text to string variable "result" and then assigning it to lblStatus.Text. But the Text is not updating in the Browser. Please, Help me Update the Text in the TextBox.
