由客户端用C#和WMI计数打印的页面(Counting printed Pages by Clien

2019-08-01 13:55发布

我们的目标是像我的话题说。 我知道有很多关于这一特定问题的文章和我尝试了所有最所有的人。 但是,由于他们的不制定出对我来说,我现在试图找出为什么这个只是工作有时有有时什么也没有发生,虽然很多东西都打印出来。 所以这是我的代码,现在应该等待打印的工作,只是告诉我这件事。 而已。

private void StartMonitor()
    {

        try
        {
            var opt = new ConnectionOptions { EnablePrivileges = true };

            var scope = new ManagementScope("root\\CIMV2", opt);

            scope.Connect();

            var query = new WqlEventQuery("SELECT * FROM __InstanceOperationEvent WITHIN 60 WHERE TargetInstance ISA \"Win32_PrintJob\"");

            var watcher = new ManagementEventWatcher(query);

            Console.WriteLine("Ready to receive Printer Job events...");

            var pjEvent = watcher.WaitForNextEvent();

            if (pjEvent != null) Console.WriteLine("Event occured: " + pjEvent.Properties["PagesPrinted"]);
        }
        catch (ManagementException e)
        {
            Console.WriteLine(e.StackTrace);
            Console.WriteLine(e.ErrorCode);
            Console.WriteLine(e.ErrorInformation);
            _Error = e.Message;
            throw;
        }
    }

Answer 1:

要获得特定作业的打印页的进展情况,请尝试使用较小的轮询间隔,并使用EventArrivedEventHandler连接到WMI事件委托在异步方式处理输入的数据。

试试这个样品。

using System;
using System.Collections.Generic;
using System.Management;
using System.Text;


namespace GetWMI_Info
{
    public class EventWatcherAsync 
    {
        private void WmiEventHandler(object sender, EventArrivedEventArgs e)
        {
            Console.WriteLine("TargetInstance.Caption :         " + ((ManagementBaseObject)e.NewEvent.Properties["TargetInstance"].Value)["Caption"]);
            Console.WriteLine("TargetInstance.JobStatus :       " + ((ManagementBaseObject)e.NewEvent.Properties["TargetInstance"].Value)["JobStatus"]);
            Console.WriteLine("TargetInstance.PagesPrinted :    " + ((ManagementBaseObject)e.NewEvent.Properties["TargetInstance"].Value)["PagesPrinted"]);
            Console.WriteLine("TargetInstance.Status :          " + ((ManagementBaseObject)e.NewEvent.Properties["TargetInstance"].Value)["Status"]);

        }

        public EventWatcherAsync()
        {
            try
            {
                string ComputerName = "localhost";
                string WmiQuery;
                ManagementEventWatcher Watcher;
                ManagementScope Scope;   


                if (!ComputerName.Equals("localhost", StringComparison.OrdinalIgnoreCase)) 
                {
                    ConnectionOptions Conn = new ConnectionOptions();
                    Conn.Username  = "";
                    Conn.Password  = "";
                    Conn.Authority = "ntlmdomain:DOMAIN";
                    Scope = new ManagementScope(String.Format("\\\\{0}\\root\\CIMV2", ComputerName), Conn);
                }
                else
                    Scope = new ManagementScope(String.Format("\\\\{0}\\root\\CIMV2", ComputerName), null);
                Scope.Connect();

                WmiQuery ="Select * From __InstanceOperationEvent Within 1 "+
                "Where TargetInstance ISA 'Win32_PrintJob' ";

                Watcher = new ManagementEventWatcher(Scope, new EventQuery(WmiQuery));
                Watcher.EventArrived += new EventArrivedEventHandler(this.WmiEventHandler);
                Watcher.Start();
                Console.Read();
                Watcher.Stop();
            }
            catch (Exception e)
            {
                Console.WriteLine("Exception {0} Trace {1}", e.Message, e.StackTrace);
            }

        }

        public static void Main(string[] args)
        {
           Console.WriteLine("Listening {0}", "__InstanceOperationEvent");
           Console.WriteLine("Press Enter to exit");
           EventWatcherAsync eventWatcher = new EventWatcherAsync();
           Console.Read();
        }
    }
}


Answer 2:

为了得到一个工作,我会尝试监控__InstanceDeletionEvents打印的总页数,我相信在那个时候Win32_PrintJob.TotalPages应该准确地显示打印的页数(不能对此进行测试,现在,对不起)。 这里也一个不错的选择:

从VB.NET监视打印机队列

如果你看一下文章的评论中,笔者还建议监察JOB_WRITTEN事件得到的打印的总数量。

如果你想监控的大型打印作业的进度,尽量监控__InstanceModificationEvents一旦创建工作,是这样的:

Select * From __InstanceModificationEvent Within 1 
Where TargetInstance Isa "Win32_PrintJob" 
And TargetInstance.PagesPrinted > PreviousInstance.PagesPrinted


文章来源: Counting printed Pages by Clients with c# and WMI
标签: c# printing wmi