asp.net Response 对象用法 返回图片
<%@ Page Language="C#" %>
<%@ import Namespace="System.Drawing" %>
<%@ import Namespace="System.Drawing.Imaging" %>
<%@ import Namespace="System.Drawing.Drawing2D" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
private void Page_Load(object sender, EventArgs e)
{
// Set the page's content type to JPEG files
// and clears all content output from the buffer stream.
Response.ContentType = "image/jpeg";
Response.Clear();
// Buffer response so that page is sent
// after processing is complete.
Response.BufferOutput = true;
// Create a font style.
Font rectangleFont = new Font(
"Arial", 10, FontStyle.Bold);
// Create integer variables.
int height = 100;
int width = 200;
// Create a random number generator and create
// variable values based on it.
Random r = new Random();
int x = r.Next(75);
int a = r.Next(155);
int x1 = r.Next(100);
// Create a bitmap and use it to create a
// Graphics object.
Bitmap bmp = new Bitmap(
width, height, PixelFormat.Format24bppRgb);
Graphics g = Graphics.FromImage(bmp);
g.SmoothingMode = SmoothingMode.AntiAlias;
g.Clear(Color.LightGray);
// Use the Graphics object to draw three rectangles.
g.DrawRectangle(Pens.White, 1, 1, width-3, height-3);
g.DrawRectangle(Pens.Aquamarine, 2, 2, width-3, height-3);
g.DrawRectangle(Pens.Black, 0, 0, width, height);
// Use the Graphics object to write a string
// on the rectangles.
g.DrawString(
"ASP.NET Samples", rectangleFont,
SystemBrushes.WindowText, new PointF(10, 40));
// Apply color to two of the rectangles.
g.FillRectangle(
new SolidBrush(
Color.FromArgb(a, 255, 128, 255)),
x, 20, 100, 50);
g.FillRectangle(
new LinearGradientBrush(
new Point(x, 10),
new Point(x1 + 75, 50 + 30),
Color.FromArgb(128, 0, 0, 128),
Color.FromArgb(255, 255, 255, 240)),
x1, 50, 75, 30);
// Save the bitmap to the response stream and
// convert it to JPEG format.
bmp.Save(Response.OutputStream, ImageFormat.Jpeg);
// Release memory used by the Graphics object
// and the bitmap.
g.Dispose();
bmp.Dispose();
// Send the output to the client.
Response.Flush();
}
</script>
<html >
<head>
<title>ASP.NET Example</title>
</head>
<body>
<form id="form1" runat="server">
</form>
</body>
</html>
