Export (0) Print
Expand All

HttpResponse.Flush Method

Sends all currently buffered output to the client.

Namespace:  System.Web
Assembly:  System.Web (in System.Web.dll)

public void Flush()

ExceptionCondition
HttpException

The cache is flushed after the response has been sent.

Forces all currently buffered output to be sent to the client. The Flush method can be called multiple times during request processing.

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. It then 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)
    {
        // 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 xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>ASP.NET Example</title>
</head>
<body>
    <form id="form1" runat="server">
    </form>
</body>
</html>

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Show:
© 2014 Microsoft