HttpResponse.OutputStream 属性
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
实现到传出 HTTP 内容主体的二进制输出。
public:
property System::IO::Stream ^ OutputStream { System::IO::Stream ^ get(); };
public System.IO.Stream OutputStream { get; }
member this.OutputStream : System.IO.Stream
Public ReadOnly Property OutputStream As Stream
属性值
表示传出 HTTP 内容主体的原始内容的 IO Stream。
例外
OutputStream
不可用。
示例
以下示例调用 Save 方法将 对象保存到 BitmapOutputStream 属性,并将图像转换为 JPEG 格式。 然后,代码对 Bitmap 对象和 Graphics 对象调用 Dispose 方法,释放它们使用的资源。 最后,代码调用 Flush 方法,将响应的内容发送到请求客户端。
有关完整示例,请参阅 HttpResponse 类。
<%@ 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)
{
// <snippet2>
// 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;
// </snippet2>
// 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);
// <snippet3>
// 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();
// </snippet3>
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ASP.NET Example</title>
</head>
<body>
<form id="form1" runat="server">
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ 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 Sub Page_Load(sender As Object, e As EventArgs)
' <snippet2>
' 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
' </snippet2>
' Create a font style.
Dim rectangleFont As New Font( _
"Arial", 10, FontStyle.Bold)
' Create integer variables.
Dim height As Integer = 100
Dim width As Integer = 200
' Create a random number generator and create
' variable values based on it.
Dim r As New Random()
Dim x As Integer = r.Next(75)
Dim a As Integer = r.Next(155)
Dim x1 As Integer = r.Next(100)
' Create a bitmap and use it to create a
' Graphics object.
Dim bmp As New Bitmap( _
width, height, PixelFormat.Format24bppRgb)
Dim g As Graphics = 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)
' <snippet3>
' 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()
' </snippet3>
End Sub 'Page_Load
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>ASP.NET Example</title>
</head>
<body>
<form id="form1" runat="server">
</form>
</body>
</html>
注解
从 .NET Framework 版本 2.0 开始,使用 Stream.Write(Byte[], Int32, Int32) 属性返回OutputStream的 IO 流的 方法时,可能会引发以下异常:
ArgumentOutOfRangeException,如果
offset
或count
参数为负值,或者buffer
如果参数的长度减去,则offset
参数小于或等于零。ArgumentNullException如果参数为 ,则为
buffer
null
。