如何使用此自定義印刷類獲得標籤打印？

Question

下面的代碼就是我試圖用來將數據打印到打印機上的代碼。數據正在打印，但標籤不打印。我的字符串，我印像這樣：

string textToPrint = "Member Number\tAddress\tCity\tState"; 

但它打印時，它看起來像這樣Member NumberAddressCityState。

我在互聯網上發現了這個打印機類，除了打印標籤外，它似乎工作（字符在報告上打印出來）。我怎樣才能確保標籤打印？

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Drawing; 
using System.Drawing.Printing; 

namespace HighLowReport 
{ 
    public class PCPrint : System.Drawing.Printing.PrintDocument 
    { 
     //Property variable for the font the user wishes to use 
     private Font _font; 

     //Property variable for the text to be printed 
     private string _text; 

     //Property to hold the text that is to be printed 
     public string TextToPrint 
     { 
      get { return _text; } 
      set { _text = value; } 
     } 

     //Property to hold the font the user wishes to use 
     public Font PrinterFont 
     { 
      get { return _font; } 
      set { _font = value; } 
     } 

     // Static variable to hold the current character 
     // we're currently dealing with. 
     static int curChar; 

     // Empty constructor 
     public PCPrint() 
      : base() 
     { 
      // set the file stream 
      // Instantiate out Text property to an empty string 
      _text = string.Empty; 
     } 

     // Constructor to initialize our printer object 
     // and the text it's supposed to be printing 
     public PCPrint(string str) 
      : base() 
     { 
      // Set the file stream 
      // Set our text property value 
      _text = str; 
     } 

     protected override void OnBeginPrint(System.Drawing.Printing.PrintEventArgs e) 
     { 
      // Run base code 
      base.OnBeginPrint(e); 

      // Check to see if the user provided a font 
      // if they didn't the we default to Times New Roman 
      if (_font == null) 
      { 
       _font = new Font("Times New Roman", 10); 
      } 
     } 

     // Override the default OnPrintPage method of the PrintDocument 
     protected override void OnPrintPage(System.Drawing.Printing.PrintPageEventArgs e) 
     { 
      // Run base code 
      base.OnPrintPage(e); 

      // declare local variables needed 
      int printHeight; 
      int printWidth; 
      int leftMargin; 
      int rightMargin; 
      Int32 lines; 
      Int32 chars; 

      // Set print area size and margins 
      {     
       printHeight = base.DefaultPageSettings.PaperSize.Height - base.DefaultPageSettings.Margins.Top - base.DefaultPageSettings.Margins.Bottom; 
       printWidth = base.DefaultPageSettings.PaperSize.Width = base.DefaultPageSettings.Margins.Left - base.DefaultPageSettings.Margins.Right; 
       leftMargin = base.DefaultPageSettings.Margins.Left; //X 
       rightMargin = base.DefaultPageSettings.Margins.Right; //Y 
      } 

      // Check if the user selected to print in Landscape mode 
      // if they did then we need to swap height/width parameters 
      if (base.DefaultPageSettings.Landscape) 
      { 
       int tmp; 
       tmp = printHeight; 
       printHeight = printWidth; 
       printWidth = tmp; 
      } 

      // Now we need to determine the total number of lines 
      // we're going to be printing 
      Int32 numLines = (int)printHeight/PrinterFont.Height; 

      // Create a rectangle printing area for our document 
      RectangleF printArea = new RectangleF(leftMargin, rightMargin, printWidth, printHeight); 

      // Use StringFormat class for the text layout of our document 
      StringFormat format = new StringFormat(StringFormatFlags.LineLimit); 

      // Fit as many characters as we can into the print area 

      e.Graphics.MeasureString(_text.Substring(RemoveZeros(ref curChar)), PrinterFont, new SizeF(printWidth, printHeight), format, out chars, out lines); 

      // Print the page 
      e.Graphics.DrawString(_text.Substring(RemoveZeros(ref curChar)), PrinterFont, Brushes.Black, printArea, format); 

      // Increase current char count 
      curChar += chars; 

      // Determine if there is more text to print, if 
      // there is then tell the printer there is more coming 
      if (curChar < _text.Length) 
      { 
       e.HasMorePages = true; 
      } 
      else 
      { 
       e.HasMorePages = false; 
       curChar = 0; 
      } 
     } 

     // Function to replace any zeros in the size to a 1 
     // Zeros will mess up the printing area 
     public int RemoveZeros(ref int value) 
     { 
      // Check the value passed into the function 
      // If the value is a 0 (zero) then return a 1, 
      // otherwise return the value passed in 
      while (_text[value] == '\0') 
      { 
       value++; 
      } 
      return value; 
     } 
    } 
} 

Answer 1

對於您的格式的StringFormat變量，你必須增加一個陣列的製表位：

StringFormat format = new StringFormat(StringFormatFlags.LineLimit); 
float[] formatTabs = { 10.0f, 20.0f }; 
format.SetTabStops(0.0f, formatTabs);