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Accepted
Alexis Gonzalez
Asked: 2020-03-17 09:31:47 +0800 CST 2020-03-17 09:31:47 +0800 CST

RFID reader connected to USB port

  • 772

I have a project but it is in Windows Form and I am a beginner in that environment. I have the following code to try to read data from an RFID proximity card reader and show the ID of said card in a textbox, the reader is connected by USB, I would like to know if someone can help me.

    namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {

        private SerialPort RFID;

        public Form1()
        {
            InitializeComponent();

            SerialPort serialPort = new SerialPort();
            RFID = serialPort;
            RFID.PortName = "COM1";
            RFID.BaudRate = 9600;
            RFID.DataBits = 8;
            RFID.Parity = Parity.None;
            RFID.StopBits = StopBits.One;
            RFID.Open();
            RFID.DataReceived += new SerialDataReceivedEventHandler(RFID_DataReceived);
            prueba();
        }


        private void prueba()
        {
            textBox2.Text = "test";
        }

        private void RFID_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            MessageBox.Show("Inica Componentes");
            string data = RFID.ReadExisting();
            textBox2 .Text = "77777";
        }

       }
    }
windows-forms

1 Answers

  1. Best Answer

    look at this portion of code, I use it to connect and obtain data from a scale through the serial port, I hope it helps guide you to the right side.

    using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO.Ports;
using System.Threading;  

private delegate void DelegadoAccesso(string accion);
void sp_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        if (this.Enabled == true)
        {
            Thread.Sleep(500);
            string data = serialPort1.ReadExisting();
            this.BeginInvoke(new DelegadoAccesso(si_DataReceived), new object[] { data });
        }

    }

    private void si_DataReceived(string accion)
    {
        //string pesoActual = accion.Substring(2, 6).Trim();
        if (accion.Contains("GS") && accion.Contains("+"))
        {
            label3.Text = accion;
            label3.BackColor = Color.Green;
        }
        else if(accion.Contains("-") || accion.Contains("GS"))
        {
            label3.BackColor = Color.Red;
            label3.Text = accion;
            //label3.Text = "0";
        }
        else if (accion.Contains("G"))
        {
            label3.BackColor = Color.Red;
        }
         //accion.Trim();
    }
    private void Form1_Load(object sender, EventArgs e)
    {
        try
        {
            serialPort1 = new SerialPort("COM1", 9600, Parity.None, 8, StopBits.One);
            serialPort1.Handshake = Handshake.None;
            serialPort1.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived);
            serialPort1.ReadTimeout = 500;
            serialPort1.WriteTimeout = 500;
            serialPort1.Open();
            label2.Text = "Conectado";
            serialPort1.Write("0P");//aqui yo le estoy pidiendo datos constantemente, lo puede borrar
        }
        catch (Exception ex)
        {
            MessageBox.Show("Error: El dispostivo de medición no esta conectado\n" + ex.Message,"Bascula Error");
        }
    }

    Give it a review and adapt it to your needs, this code works for me.
    Luck.

    • 1