Form app doesnt loading
Hi there,I tried to make a simple COM port interface with forms,altought there is no error it doesnt loading.Here is my code:
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;
namespace COMv1
{
public partial class Form1 : Form
{
private SerialPort port;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
string[] ports = SerialPort.GetPortNames();
for (int i=0;i< ports.Length;i++)
{
listBox1.Items.Add(ports[i]);
}
label1.Text = "Select port";
this.Show();
while (listBox1.SelectedIndex == -1)
{
}
port = new SerialPort(listBox1.GetItemText(listBox1.SelectedItem), 9600);
port.Open();
if (port.IsOpen)
{
label1.ForeColor = Color.Green;
}
else
{
label1.ForeColor = Color.Red;
}
this.Show();
}
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
string veri = textBox1.Text;
textBox1.Clear();
port.Write(veri);
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
}
}
9 Replies
Don't use synchronous methods in the load event
Like while rgiht?
You also have an infinite loop from what I can see
Why are you calling
this.Show() multiple times?Because it will stuck in while and dont display things before it
Remove the while loop, see if that solves anything.
Actually, remove everything regarding COM connection in the load
yes,It fixed it thank you
then,how can I wait util I select smetihnig from listbox?
It shouldn't be there either way, prefer a button like "Connect" or something of that sort.
if the code is blocking you could use threads and work your way from there.
If you need to work with the GUI, you can use
yourControl.Invoke(..) if the UI code isn't called from the UI Thread.
https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.control.invoke?view=windowsdesktop-8.0Thanks a lot,I will try it:catlove:
However. Avoid relying on the UI to do everything, such as this line
listBox1.GetItemText(listBox1.SelectedItem). Otherwise it may bring you pain in the future.