如何连接打印机

Question

我正在尝试连接打印机，但状态总是显示错误。如何编程连接打印机。

namespace CustomFunction
{
    public class Custom
    {
        public Custom();
        public string PaperStatus();
        public string PrinterModel();
    }
}
namespace CustomPrinterStatusCheck
{
    public class Program
    { 
       
        private enum PrinterStatus
        {
            PaperPresent, 
            NearPaperEnd, //4
            paperAbsent, //5
            Error, // typically printer fault or not founds
            Default // have not do any check since kiosk is up
        }
        private static string resultSaveLocation = "";
        private static string applicationRunningMode = "";
        private static readonly ILog ApplicationExceptionLogger = LogManager.GetLogger("APP.ExceptionLogger");
        public static void Main(string[] args)
        {
            try
            {
                Bootstrap();
                string value = "";
                PrinterStatus currentStatus = GetPrinterPaperStatus();     
                switch (currentStatus)
                {
                    case PrinterStatus.Default:
                       value = "DFT";
                        break;
                    case PrinterStatus.NearPaperEnd:
                        value = "NPE";
                        break;
                    case PrinterStatus.paperAbsent:
                        value = "PRA";
                        break;
                    case PrinterStatus.PaperPresent:
                        value = "PRP";
                        break;
                    case PrinterStatus.Error:
                        value = "ERR";
                        break;
                }
                Console.WriteLine("Printer Status: " + currentStatus.ToString() + " Code:" + value);
                WriteResultToTextfile(value);
            }
            catch (Exception ex)
            {
                // display the result in console window
                Console.WriteLine(ex.Message);
                // write the exceptoin / error to log file
                ApplicationExceptionLogger.Error(ex);
            }
            finally
            {
                // display the result in console window
                Console.WriteLine("Operation completed");
                // if application is running in text mode, console window will 
                // not closed by itself
                if (applicationRunningMode == "TEST")
                {
                    Console.ReadLine();
                }
            }
            
        }
        /// <summary>
        /// clean the file content and write -1 to indicate the failure of validating user
        /// </summary>
        private static void WriteResultToTextfile(string textToWrite)
        {
            string filePath = System.AppDomain.CurrentDomain.BaseDirectory + resultSaveLocation;
            File.WriteAllText(filePath, textToWrite);
        }
        /// <summary>
        /// setting up the application
        /// </summary>
        private static void Bootstrap()
        {
            XmlConfigurator.Configure();
            resultSaveLocation = ConfigurationManager.AppSettings["ResultOutputLocation"].ToString();
            applicationRunningMode = ConfigurationManager.AppSettings["ApplicationRunningMode"].ToString();
        }
        /// <summary>
        /// function to query custom printer status 
        /// </summary>
        /// <returns></returns>
        private static PrinterStatus GetPrinterPaperStatus()
        {
            PrinterStatus currentPrinterStatus = PrinterStatus.Default;
            
            CustomFunction.Custom printer = new Custom();
            string printerStatus = printer.PaperStatus();
            if (printerStatus.Contains("0"))
            {
                currentPrinterStatus = PrinterStatus.PaperPresent;
            }
            else if (printerStatus.Contains("4"))
            {
                currentPrinterStatus = PrinterStatus.NearPaperEnd;
            }
            else if (printerStatus.Contains("5"))
            {
                currentPrinterStatus = PrinterStatus.paperAbsent;
            }
            else if (printerStatus.Contains("Error"))
            {
                currentPrinterStatus = PrinterStatus.Error;
            }
            return currentPrinterStatus;
        }
        
   
    }

}

Answer 1

这是一个很好的例子。

欢迎来到c#打印教程

在过去，用微软语言打印文档很容易。有了像Visual Basic这样的语言，它就是一台简单的打印机。打印的电话。在那些日子里，在那种语言中，我们会调用它，文档就会打印出来，但由于那不是面向对象的语言，我们无法控制任何东西。

快进到神奇的2000年，微软在这一年推出了c#。有了c#，就不再有Printer了。用于打印文档的打印解决方案。由于c#是一种面向对象的语言，你现在可以控制整个打印过程，从字体到字体大小，到页面的方向(横向，纵向)，再到打印区域的大小(页面大小)，这当然需要程序员做一些工作。这就是本教程的目的，也是我每天至少问一次如何完成这个任务的事实。