BarCode条形码基于C# GDI+ 的实现方法详解

条形码在生活中的应用非常广泛，具体的条形码知识大家自行百度，了解条形码知识对理解下面的代码是必要的。如果只是应用的话，直接拿去就可以用了。
废话不多说，上代码


代码如下:

public Bitmap GetCode39(string sourceCode)
         {
             int leftMargin = 5;
             int topMargin = 0;
             int thickLength = 2;
             int narrowLength = 1;
             int barCodeHeight = 35;
             int intSourceLength = sourceCode.Length;
             string strEncode = "010010100"; //添加起始码“*”.
             var font = new System.Drawing.Font("Segoe UI", 5);

string AlphaBet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. $/+%*";

string[] Code39 =
             {
                 /* 0 */ "000110100", 
                 /* 1 */ "100100001", 
                 /* 2 */ "001100001", 
                 /* 3 */ "101100000",
                 /* 4 */ "000110001", 
                 /* 5 */ "100110000", 
                 /* 6 */ "001110000", 
                 /* 7 */ "000100101",
                 /* 8 */ "100100100", 
                 /* 9 */ "001100100", 
                 /* A */ "100001001", 
                 /* B */ "001001001",
                 /* C */ "101001000", 
                 /* D */ "000011001", 
                 /* E */ "100011000", 
                 /* F */ "001011000",
                 /* G */ "000001101", 
                 /* H */ "100001100", 
                 /* I */ "001001100", 
                 /* J */ "000011100",
                 /* K */ "100000011", 
                 /* L */ "001000011", 
                 /* M */ "101000010", 
                 /* N */ "000010011",
                 /* O */ "100010010", 
                 /* P */ "001010010", 
                 /* Q */ "000000111", 
                 /* R */ "100000110",
                 /* S */ "001000110", 
                 /* T */ "000010110", 
                 /* U */ "110000001", 
                 /* V */ "011000001",
                 /* W */ "111000000", 
                 /* X */ "010010001", 
                 /* Y */ "110010000", 
                 /* Z */ "011010000",
                 /* - */ "010000101", 
                 /* . */ "110000100", 
                 /*' '*/ "011000100",
                 /* $ */ "010101000",
                 /* / */ "010100010", 
                 /* + */ "010001010", 
                 /* % */ "000101010", 
                 /* * */ "010010100" 
             };
             sourceCode = sourceCode.ToUpper();

Bitmap objBitmap = new Bitmap(
               ((thickLength * 3 + narrowLength * 7) * (intSourceLength + 2)) + (leftMargin * 2),
               barCodeHeight + (topMargin * 2));
             Graphics objGraphics = Graphics.FromImage(objBitmap);

objGraphics.FillRectangle(Brushes.White, 0, 0, objBitmap.Width, objBitmap.Height);

for (int i = 0; i < intSourceLength; i++)
             {
                 //非法字符校验
                 if (AlphaBet.IndexOf(sourceCode[i]) == -1 || sourceCode[i] == '*')
                 {
                     objGraphics.DrawString("Invalid Bar Code",
                       SystemFonts.DefaultFont, Brushes.Red, leftMargin, topMargin);
                     return objBitmap;
                 }
                 //编码
                 strEncode = string.Format("{0}0{1}", strEncode,
                  Code39[AlphaBet.IndexOf(sourceCode[i])]);
             }

strEncode = string.Format("{0}0010010100", strEncode); //添加结束码“*”

int intEncodeLength = strEncode.Length;
             int intBarWidth;

for (int i = 0; i < intEncodeLength; i++) //绘制 Code39 barcode
             {
                 intBarWidth = strEncode[i] == '1' ? thickLength : narrowLength;
                 objGraphics.FillRectangle(i % 2 == 0 ? Brushes.Black : Brushes.White,
                  leftMargin, topMargin, intBarWidth, barCodeHeight);
                 leftMargin += intBarWidth;
             }

//绘制 明码
             SizeF sizeF = objGraphics.MeasureString(sourceCode, font);
             float x=(objBitmap.Width - sizeF.Width) / 2;
             float y = objBitmap.Height - sizeF.Height;
             objGraphics.FillRectangle(Brushes.White, x, y, sizeF.Width, sizeF.Height);
             objGraphics.DrawString(sourceCode, font, Brushes.Black, x, y);

return objBitmap;
         }

新建一个Winform程序拖一个PictureBox控件，然后把方法返回的图片绑到PictureBox上，就可以看到结果了。

以上代码需要引用 System.Drawing 命名空间。

顺带提一句，还有一种最简单的办法就是下载条形码字体，然后输出的时候设定字体为条形码字体，显示的就是条形码了。不过你不能要求每个客户机都装这种字体。这个是个明显的缺陷,所以不推荐使用这种方法。