HttpResponse.OutputStream Property

Reference

Definition

Namespace:: System.Web

Assembly:: System.Web.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Enables binary output to the outgoing HTTP content body.

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

Property Value

Stream

An IO Stream representing the raw contents of the outgoing HTTP content body.

Exceptions

HttpException

OutputStream is not available.

Examples

The following example calls the Save method to save a Bitmap object to the OutputStream property, and converts the image to the JPEG format. The code then calls the Dispose method on the Bitmap object and a Graphics object, releasing the resources that they were using. Finally, the code calls the Flush method to send the content of the response to the requesting client.

For a complete example, see the HttpResponse class.

<%@ 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>

Remarks

Starting with the .NET Framework version 2.0, when you use the Stream.Write(Byte[], Int32, Int32) method of the IO stream returned by the OutputStream property, the following exceptions might be thrown:

ArgumentOutOfRangeException, if the offset or count parameter is negative or if the buffer parameter's length minus the offset parameter is less than or equal to zero.
ArgumentNullException, if the buffer parameter is null.

Applies to

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