监听打印机状态

【实例截图】

【核心代码】

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

namespace App.Printer.Monitor.Solution
{
    public partial class MainForm : Form
    {
        PrintQueueMonitor pqm = null;
        public MainForm()
        {
            InitializeComponent();
        }
        /// <summary>
        /// 窗口加载
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void MainForm_Load(object sender, EventArgs e)
        {
            PrintServer ps = new PrintServer();
            foreach (PrintQueue pq in ps.GetPrintQueues())
                cmbPrinters.Items.Add(pq.Name);
        }
        /// <summary>
        /// 开始监听
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            if (cmbPrinters.Enabled)
            {
                if (cmbPrinters.Text.Trim() == "") return;
                pqm = new PrintQueueMonitor(cmbPrinters.Text.Trim());
                pqm.OnJobStatusChange  = new PrintJobStatusChanged(pqm_OnJobStatusChange);
                cmbPrinters.Enabled = false;
                btnMonitor.Text = "停止监听.....";
            }
            else
            {
                if (pqm != null) pqm.Stop();
                pqm = null;
                cmbPrinters.Enabled = true;
                btnMonitor.Text = "开始监听.....";
            }
        }
        /// <summary>
        /// 改变事件
        /// </summary>
        /// <param name="Sender"></param>
        /// <param name="e"></param>
        void pqm_OnJobStatusChange(object Sender, PrintJobChangeEventArgs e)
        {
            #region 注释掉
            //if (e.JobInfo != null && e.JobInfo.JobStream != null)
            //{
            //    string text1 = GetStreamToString(e.JobInfo.JobStream);
            //}

            //MethodInvoker invoker = () =>
            //{
            //    listmessagebox.Items.Add(e.JobID   " - "   e.JobName   " - "   e.JobStatus);
            //};
            //if (listmessagebox.InvokeRequired)
            //{
            //    Invoke(invoker);
            //}
            //else
            //{
            //    invoker();
            //}
            #endregion

            listmessagebox.Invoke(new PrintMessageLog((node) =>
            {
                listmessagebox.Items.Add(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff")   "  "   node.JobID   " 文档名称: "   node.JobName   " 状态："   node.JobStatus);
                listmessagebox.SelectedIndex = listmessagebox.Items.Count - 1;
            }), new object[] { e });

        }
        public delegate void PrintMessageLog(PrintJobChangeEventArgs eNode);

        public string GetStreamToString(Stream _Stream)
        {
            if (_Stream == null)
                return "";
            StreamReader reader = new StreamReader(_Stream);
            string text = reader.ReadToEnd();
            return text;
        }
    }
}