本文转自：https://www.cnblogs.com/rockyhm/p/3434200.html
最近做一个B/S的项目，需要读取电子秤的值，之前一直没做过，也没有经验，于是在网上找到很多 大致分两种
详情见 使用JS获得串口数据 http://blog.csdn.net/xuing/article/details/6688306 但是小弟用这两种办法都获取到数据
串口配置如下：
1 serialPort1.PortName = "COM1"; //端口名称
2 serialPort1.BaudRate = 1200; //波特率
3 serialPort1.Parity = Parity.None; //奇偶效验
4 serialPort1.StopBits = StopBits.One; //效验
5 serialPort1.DataBits = 8; //每个字节的数据位长度
最后换种思路：使用C#写一个ActiveX控件（吉日老师提醒）最后嵌入网页中读取数据 如下：
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
namespace MyActive
{
//Guid唯一，不可变更，否则将无法通过IE浏览器的ActiveX控件的安全认证
[ComImport, Guid("CB5BDC81-93C1-11CF-8F20-00805F2CD064")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IObjectSafety
{
[PreserveSig]
void GetInterfacceSafyOptions(int riid,out int pdwSupportedOptions,out int pdwEnabledOptions);
}
}
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace MyActiveX
{
[Guid("218849AF-1B2C-457B-ACD5-B42AC8D17EB7"), ComVisible(true)]
public partial class MyActiveXControl : UserControl,IObjectSafety
{
public MyActiveXControl()
{
InitializeComponent();
}
#region IObjectSafety 成员 用于ActiveX控件安全信任
public void GetInterfacceSafyOptions(int riid, out int pdwSupportedOptions, out int pdwEnabledOptions)
{
pdwSupportedOptions = 1;
pdwEnabledOptions = 2;
}
public void SetInterfaceSafetyOptions(int riid, int dwOptionsSetMask, int dwEnabledOptions)
{
throw new NotImplementedException();
}
#endregion
}
} 至此 Active控件制作完毕 下面我们添加文本框、按钮、SerialPort、Timer控件进行测试 
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.IO.Ports;
using System.Text;
using System.Threading;
using System.Windows.Forms;
using System.Runtime.InteropServices;
using MyActive;
namespace MyActiveX
{
//不可改变
[Guid("218849AF-1B2C-457B-ACD5-B42AC8D17EB7"), ComVisible(true)]
public partial class MyActiveXControl : UserControl, IObjectSafety
{
public MyActiveXControl()
{
InitializeComponent();
}
public delegate void HandleInterfaceUpdataDelegate(string text);//定义一个委托
private HandleInterfaceUpdataDelegate interfaceUpdataHandle;//声明
bool isClose = false;//是否关闭
#region IObjectSafety 成员 用于ActiveX控件安全信任
public void GetInterfacceSafyOptions(int riid, out int pdwSupportedOptions, out int pdwEnabledOptions)
{
pdwSupportedOptions = 1;
pdwEnabledOptions = 2;
}
public void SetInterfaceSafetyOptions(int riid, int dwOptionsSetMask, int dwEnabledOptions)
{
throw new NotImplementedException();
}
#endregion
private void button1_Click(object sender, EventArgs e)
{
try
{
interfaceUpdataHandle = new HandleInterfaceUpdataDelegate(UpdateTextBox);//实例化委托对象
serialPort1.DataReceived += new SerialDataReceivedEventHandler(serialPort1_DataReceived);
if (!serialPort1.IsOpen)
{
serialPort1.Open();
}
button2.Enabled = true;
button1.Enabled=false;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
return;
}
timer1.Enabled = true;
}
/// <summary>
/// 控件加载事件
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void MyActiveXControl_Load(object sender, EventArgs e)
{
setOrgComb();
}
/// <summary>
/// 初始化串口
/// </summary>
private void setOrgComb()
{
serialPort1.PortName = "COM1"; //端口名称
serialPort1.BaudRate = 1200; //波特率
serialPort1.Parity = Parity.None; //奇偶效验
serialPort1.StopBits = StopBits.One; //效验
serialPort1.DataBits = 8; //每个字节的数据位长度
}
/// <summary>
/// 更新数据
/// </summary>
/// <param name="text"></param>
private void UpdateTextBox(string text)
{
//richTextBox1.Text = text + "\n\t" + richTextBox1.Text;
richTextBox1.Text = text;
}
/// <summary>
/// 接收数据是发生
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
//获取接收缓冲区中数据的字节数
if (serialPort1.BytesToRead > 5)
{
string strTemp = serialPort1.ReadExisting();//读取串口
double weight = -1;//获取到的重量
foreach (string str in strTemp.Split('='))//获取稳定的值
{
double flog = 0;
//数据是否正常
if(double.TryParse(str, out flog)&&str.IndexOf('.')>0&&str[str.Length-1]!='.')
{
//数据转换 串口获取到的数据是倒叙的 因此进行反转
char[] charArray = str.ToCharArray();
Array.Reverse(charArray);
string left = new string(charArray).Split('.')[0];
string right = new string(charArray).Split('.')[1];
if (right.Length==2)
{
weight = int.Parse(left) + int.Parse(right) / 100.0;
}
}
}
if(weight>=0)
{
//在拥有控件的基础窗口句柄的线程上，用指定的参数列表执行指定委托。
this.Invoke(interfaceUpdataHandle, weight.ToString());//取到数据 更新
}
}
}
private void button2_Click(object sender, EventArgs e)
{
try
{
button1.Enabled = true;
button2.Enabled = false;
serialPort1.Close();
timer1.Enabled = false;
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
private void timer1_Tick(object sender, EventArgs e)
{
if (isClose)
{
return;
}
try
{
string send = "" + (char)(27) + 'p';
send = serialPort1.ReadExisting();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
button2_Click(null, null);
}
}
}
}
9. 生成安装程序，在项目MyActiveX\Setup1\Debug下找到Setup1.msi，双击安装它。
然后在该目录下新建一个html文件(test.html)用于测试我们的ActiceX控件。HTML代码如下：
<html>
<title>Powered by yyzq.net Email:yq@yyzq.net</title>
<head>
</head>
<body>
<div>
<object id="yyzq" classid="clsid:218849AF-1B2C-457B-ACD5-B42AC8D17EB7"
width="320"
height="240"
codebase="Setup1.msi">
</object>
</div>
</body>
</html> 在IE浏览器下打开test.html，点击start 开始监听
