作者: BUILDER.COM
Wednesday, April 9 2003 11:23 AM
X-Bitmap(XBM)是一种古老但通用的图像文件格式,它与现在的许多Web浏览器都兼容。X-Windows图形界面(UNIX和Linux常用的GUI)的C代码库xlib中有一个组件专门描述了它的规范。我将解释XBM格式的工作原理,然后向你展示一种更有趣的使用它的方法:在客户端创建动态图像。文章中的代码可以在此下载。
<!--#include file="num.asp"-->
<%
Dim Image
Dim Width, Height
Dim num
Dim digtal
Dim Length
Dim sort
Length = 10 '自定计数器长度
Redim sort( Length )
num = 62275 '计数器的值
digital = ""
For I = 1 To Length -Len( num ) '补0
digital = digital & "0"
Next
For I = 1 To Len( num )
digital = digital & Mid( num, I, 1 )
Next
For I = 1 To Len( digital )
sort(I) = Mid( digital, I, 1 )
Next
Width = 8 * Len( digital ) '图像的宽度
Height = 10 '图像的高度,在本例中为固定值
Response.ContentType="image/x-xbitmap"
hc=chr(13) & chr(10)
Image = "#define counter_width " & Width & hc
Image = Image & "#define counter_height " & Height & hc
Image = Image & "static unsigned char counter_bits[]={" & hc
For I = 1 To Height
For J = 1 To Length
Image = Image & a(sort(J),I) & ","
Next
Next