在我們的程序開發中，有些行業用到座機的來電彈屏，而C#作為微軟的一個重要開發工具，應用廣泛，本代碼實現了C#調用DLL實現來電彈屏（以中盛座機來電顯示盒為例，該盒子穩定可靠，編程簡單）。

using ServiceDesk;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using
 
 System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WinF
{
    public partial class Form1 : Form
    {
　　　　　　//最關鍵的是下面4行調用DLL的聲明
        [DllImport("ZSCIDUDP.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Ansi, EntryPoint = "
 
ZSCIDInit")]
        public static extern int ZSCIDInit(string AUDPS_IP, int AUDPS_Port, bool AIsSendState); 

        [DllImport("ZSCIDUDP.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Ansi, EntryPoint = "ZSCIDFree")]
        public static extern void ZSCIDFree(int ARef);

        
 
public int laidianCount { get; set; }
        public int FRef { get; set; }


        public void zsinit()
        {
            FRef = ZSCIDInit("127.0.0.1", 9013, false);//第一個參數是來電後要發到UDP監聽的IP，第二個參數是UDP監聽的端口號
        }

        public void zsfree()
        {
            if (FRef > 0)
            {
                ZSCIDFree(FRef);
                FRef = 0;
            }
        }

        public Form1()
        {
            InitializeComponent();
            
            UdpLisenter(); //這裏實現UDP監聽
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            zsinit();
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            free();
        }

        private void btn_init_Click(object sender, EventArgs e)
        {
            init();
        }

        private void btn_free_Click(object sender, EventArgs e)
        {
            free();
        }

        void init()
        {
            try
            {
                zsinit();

                btn_free.Enabled = true;
                btn_init.Enabled = false;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "ZSCIDInit異常");
            }
            finally
            {
                txt_FRef.AppendText("初始化【FRef=" + FRef + "】" + Environment.NewLine);
            }
        }

        void free()
        {
            try
            {
                txt_FRef.AppendText("釋放前【FRef=" + FRef + "】" + Environment.NewLine);
                zsfree();

                btn_free.Enabled = false;
                btn_init.Enabled = true;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "ZSCIDFree異常");
            }
            finally
            {
                txt_FRef.AppendText("釋放後【FRef=" + FRef + "】" + Environment.NewLine);
            }
        }

       

        void StateHandler(string data)
        {
            txt_state.AppendText(data.ToString() + Environment.NewLine);
        }

        private void UdpLisenter()
        {
            Task.Factory.StartNew(() =>
            {
                int updPort = 9013;

                UdpClient listener = new UdpClient(updPort);
                listener.DontFragment = true;
                listener.EnableBroadcast = true;
                IPEndPoint RemoteIpEndPoint = new IPEndPoint(IPAddress.Loopback, updPort);

                while (true)
                {
                    try
                    {
                        byte[] bytes = listener.Receive(ref RemoteIpEndPoint);
                        string data = System.Text.Encoding.Default.GetString(bytes);

                        string PhoneNumber = getnum(data);
                        writelog(PhoneNumber);
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show(ex.Message);
                    }
                }

            }, TaskCreationOptions.LongRunning | TaskCreationOptions.PreferFairness);
        }

        string getnum(string data)
        {
            string PhoneNumber = "";
            if (!string.IsNullOrWhiteSpace(data))
            {
                string[] strs = data.Split(new string[] { "\r\n" }, StringSplitOptions.None);

                foreach (string k in strs)
                {
                    string[] tttmp = k.Split(‘=‘);
                    if (tttmp.Length > 1 && tttmp[0] == "NUM")
                        PhoneNumber = tttmp[1];
                }
            }

            return PhoneNumber;
        }
        void writelog(string number)
        {
            if (!string.IsNullOrWhiteSpace(number))
            {
                txt_udprecieve.AppendText("[" + laidianCount++ + "]: " + number + " " + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + Environment.NewLine);

                LaidianWriter wer = new LaidianWriter();
                wer.Push(number);
            }
        }
    }

    

}

C#檢測座機來電號碼實現來電彈屏的實現方法