このテキストデータがプリンタで印刷されないのはなぜですか？

Question

私はprintdocument1.print（）をしようとしています。

using System; 
using System.Collections.Generic; 
using System.ComponentModel; 
using System.Data; 
using System.Drawing; 
using System.Linq; 
using System.Text; 
using System.Windows.Forms; 
using System.Drawing.Printing; 
using System.IO; 
using System.Management; 
using System.Diagnostics; 

namespace csvform 
{ 
public partial class Form3 : Form 
{ 

     private PrintDocument printDocument1 = new PrintDocument(); 
    private string stringToPrint; 
    public Form3() 
    { 
     InitializeComponent(); 


     printDocument1.PrintPage += 
      new PrintPageEventHandler(printDocument1_PrintPage); 

    } 


    private void ReadFile() 
    { 
     string docName = "testPage.txt"; 
     string docPath = @"c:\"; 
     printDocument1.DocumentName = docName; 
     using (FileStream stream = new FileStream(docPath + 
     docName, FileMode.Open)) 
     using (StreamReader reader = new StreamReader(stream)) 
     { 
      stringToPrint = reader.ReadToEnd(); 
     } 
    } 

    private void printDocument1_PrintPage(object sender, 
    PrintPageEventArgs e) 
    { 
     int charactersOnPage = 0; 
     int linesPerPage = 0; 
     Font nf = new Font(new FontFamily("Arial"), 10, 
     System.Drawing.FontStyle.Bold); 
     // Sets the value of charactersOnPage to the number of characters 
     // of stringToPrint that will fit within the bounds of the page. 
     e.Graphics.MeasureString(stringToPrint,nf, 
      e.MarginBounds.Size, StringFormat.GenericTypographic, 
      out charactersOnPage, out linesPerPage); 

     // Draws the string within the bounds of the page 
     e.Graphics.DrawString(stringToPrint,nf, Brushes.Black, 
      e.MarginBounds, StringFormat.GenericTypographic); 

     // Remove the portion of the string that has been printed. 
     stringToPrint = stringToPrint.Substring(charactersOnPage); 

     // Check to see if more pages are to be printed. 
     e.HasMorePages = (stringToPrint.Length > 0); 
    } 

    private void button1_Click(object sender, EventArgs e) 
    { 


     ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT *   FROM Win32_Printer"); 
     string printerName = ""; 
     foreach (ManagementObject printer in searcher.Get()) 
     { 
      printerName = printer["Name"].ToString().ToLower(); 
      if (printerName.Equals(@"\\chenraqdc2.raqmiyat.local\hp color laserjet cp1510")) 
      {            
        // printDocument1.Print(); 
        try 
        { 
         // Assumes the default printer. 
         ReadFile(); 
         printDocument1.Print(); 
        } 
        catch (Exception ex) 
        { 
         MessageBox.Show("An error occurred while printing", ex.ToString()); 
        }      

      } 
     }  
    } 
} 
} 

Answer 1

For historical purposes：

システムは、ここでは任意のもの

は、コードの後ろに私のC＃コードでファイル名とシステムとしてポップアップ表示されたエラーを投げるうちに黙ってばかりの小さな模型を見せていました

// namespace declaration 
using System.Management; 

// code sample for setting default printer 

ManagementObjectCollection objManagementColl; 
// class used to invoke the query for specified management collection 
ManagementObjectSearcher objManagementSearch = new ManagementObjectSearcher("SELECT * FROM Win32_Printer"); 

// invokes the specified query and returns the resulting collection 
objManagementColl = objManagementSearch.Get(); 

foreach(ManagementObject objManage in objManagementColl) 
    { 
     if (objManage["Name"].ToString() == "RequiredPrinterName") // compares the name of printers 
      { 
      objManage.InvokeMethod("SetDefaultPrinter", null); // invoke [SetDefaultPrinter] method 
      break; 
      } 
     }