Question

您好我有这个代码来检索打印机属性：

string printerName = "PrinterName";
string query = string.Format("SELECT * from Win32_Printer " 
                                + "WHERE Name LIKE '%{0}'",
                             printerName);

ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
ManagementObjectCollection coll = searcher.Get();

foreach (ManagementObject printer in coll)
{
    foreach (PropertyData property in printer.Properties)
    {
          Console.WriteLine(string.Format("{0}: {1}", 
                                          property.Name, 
                                          property.Value));
    }
}

但我需要的属性总是返回相同的内容：

PrinterState：0

PrinterStatus：3

基本上我需要这个来检查打印机是否缺纸。我的想法是：PrinterState：4

在wxp-86和w7-64上测试返回相同的.Net 4.0

谢谢。

Answer 1

我也有这个问题，并没有简单的解决方法。

问题的原因是Windows Management Instrumentation（WMI）从 spoolsv.exe 进程检索打印机信息。因此，检索信息的可靠性完全取决于打印机驱动程序。您正在查询信息的打印机驱动程序可能绕过假脱机程序以获取状态，或者它不会将状态报告给假脱机程序进程。

Win32_Printer 将报告假脱机程序中包含的任何状态。因此，如果假脱机程序报告就绪，则它永远不会收到状态更改的数据，因为默认为 Ready 。 Win32_Printer 只是将其导出为空闲（PrinterStatus = 3或PrinterState = 0）。

Answer 2

根据msdn， Paper Out = 5

using System;
using System.Management;
using System.Windows.Forms;

namespace WMISample
{
    public class MyWMIQuery
    {
        public static void Main()
        {
            try
            {
                string printerName = "PrinterName";
                ManagementObjectSearcher searcher = 
                    new ManagementObjectSearcher("root\\CIMV2", 
                    "SELECT * FROM Win32_Printer "
                     + "WHERE Name LIKE '%{0}'", printerName);); 

                foreach (ManagementObject queryObj in searcher.Get())
                {
                    Console.WriteLine("-----------------------------------");
                    Console.WriteLine("Win32_Printer instance");
                    Console.WriteLine("-----------------------------------");
                    Console.WriteLine("PrinterStatus: {0}", queryObj["PrinterStatus"]);
                }
            }
            catch (ManagementException e)
            {
                MessageBox.Show("An error occurred while querying for WMI data: " + e.Message);
            }
        }
    }
}

Answer 3

这一行：

string query = string.Format("SELECT * from Win32_Printer " 
                            + "WHERE Name LIKE '%{0}'",
                         printerName);

尝试使用％after printername后调用它：

string query = string.Format("SELECT * from Win32_Printer " 
                            + "WHERE Name LIKE '%{0}%'",
                         printerName);

通常打印机名称为：“[printername] On [port]”

Answer 4

此外，您可以检查扩展打印机状态和其他属性；有线打印机比无线打印机（Lan，WLan，蓝牙）可以提供更多的信息。

https://docs.microsoft.com/en-us/windows/win32/cimwin32prov/win32-printer

using System;
using System.Management;
using System.Windows.Forms;

namespace PrinterSet
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

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

        private void QueryOnWMI()
        {
            try
            {
                // Common Information Model v2 (namespace)
                string scope = @"root\CIMV2";
                string printerName = printerNameTextBox.Text.Trim();
                //printerName = "%DocuCentre%";
                string query = "SELECT * FROM Win32_Printer";
                if (!string.IsNullOrEmpty(printerName))
                {
                    query += $" WHERE Name Like '%{printerName}%'";
                }
                Console.Clear();
                var searcher = new ManagementObjectSearcher(scope, query);
                var result = searcher.Get();
                if (result == null || result.Count == 0)
                {
                    Console.WriteLine($"Printer '{printerName}' not found");
                }
                var line = new string('-', 40);
                foreach (ManagementObject queryObj in result)
                {
                    Console.WriteLine(line);
                    Console.WriteLine($"Printer : {queryObj["Name"]}");
                    ushort ps = Convert.ToUInt16(queryObj["PrinterStatus"]);
                    var psEnum = (PrinterStatus)ps;
                    Console.WriteLine("PrinterStatus: {0} ({1})", psEnum, ps);
                    ps = Convert.ToUInt16(queryObj["ExtendedPrinterStatus"]);
                    var psExtended = (ExtendedPrinterStatus)ps;
                    Console.WriteLine("Extended Status: {0} ({1})", psExtended, ps);
                    //var papers = (string[])queryObj["PrinterPaperNames"];
                    //foreach (var paper in papers)
                    //{
                    //    Console.WriteLine("Paper Name: {0}", paper);
                    //}
                    Console.WriteLine(line);
                }
            }
            catch (ManagementException emx)
            {
                // TRY => NET STOP SPOOLER
                // Generic failure is thrown 
                MessageBox.Show(this, "Invalid query: " + emx.Message);
            }
        }

        public enum PrinterStatus : UInt16
        {
            Other = 1, Unknown = 2, Idle = 3, Printing= 4, Warmup = 5, StoppedPrinting = 6, Offline = 7, 
        }

        public enum ExtendedPrinterStatus : UInt16
        {
            Other = 1, Unknown = 2, Idle = 3, Printing, WarmingUp, StoppedPrinting, Offline, Paused, Error, 
            Busy, NotAvailable, Waiting, Processing, Initialization, PowerSave, PendingDeletion, IOActive, ManualFeed

        }

        private void button1_Click(object sender, EventArgs e)
        {
            QueryOnWMI();
        }
    }
}

您还可以探索Windows后台打印程序API： https://docs.microsoft.com/en-us/windows-hardware/drivers/print/introduction-to-spooler-components

和： windows-printer-driver@stackoverflow

antonio

c＃打印机属性WMI

4 个答案: