我用 C# 为我的 Arduino 做了一个小应用程序。一切正常，但问题出在我的应用程序中。用户可以在 numericUpDown 中选择他/她的 COM 端口。
它可以工作，但是如果用户选择了错误的端口并尝试连接，它就会崩溃，所以我想我需要一个 IF statmant 来提供消息。比如端口不对等，但是不知道怎么弄。我该怎么做？
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.IO.Ports;
namespace IO_Arduino_experiment_project
{
public partial class Form1 : Form
{
public static System.IO.Ports.SerialPort serialPort1;
private delegate void LineReceivedEvent(string line);
public Form1()
{
InitializeComponent();
button5.Enabled = false;
button2.Enabled = false;
button3.Enabled = false;
}
private void button1_Click(object sender, EventArgs e) // Connect Button
{
System.ComponentModel.IContainer components = new System.ComponentModel.Container();
serialPort1 = new System.IO.Ports.SerialPort(components); // Creating the new object.
serialPort1.PortName = "COM" + numericUpDown1.Value.ToString(); // Setting what port number.
serialPort1.BaudRate = 9600;
serialPort1.DtrEnable = true;
serialPort1.Open(); // Open the port for use.
button1.Text = "Connected.";
button1.Enabled = false;
numericUpDown1.Enabled = false;
button5.Enabled = true;
button2.Enabled = true;
button3.Enabled = true;
}
private void numericUpDown1_ValueChanged(object sender, EventArgs e)
{
}
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
if (serialPort1.IsOpen) serialPort1.Close();
}
private void button2_Click(object sender, EventArgs e)
{
serialPort1.Write("1");
textBox1.Text = "LED is on!";
button2.Enabled = false;
button3.Enabled = true;
}
private void button3_Click(object sender, EventArgs e)
{
serialPort1.Write("0");
textBox1.Text = "LED is off!";
button2.Enabled = true;
button3.Enabled = false;
}
private void button4_Click(object sender, EventArgs e)
{
Close();
}
private void button5_Click(object sender, EventArgs e)
{
serialPort1.Close();
button1.Enabled = true;
numericUpDown1.Enabled = true;
}
}
}