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Asp.net UpdatePanel allows you to upload images without refreshing images.

Source: Internet
Author: User
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1) Front-end
Copy codeThe Code is as follows:
<% @ Page Language = "C #" AutoEventWireup = "true" CodeFile = "Default. aspx. cs" Inherits = "_ Default" %>
<! DOCTYPE html PUBLIC "-// W3C // dtd xhtml 1.0 Transitional // EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<Html xmlns = "http://www.w3.org/1999/xhtml">
<Head runat = "server">
<Title> </title>
</Head>
<Body>
<Form id = "form1" runat = "server">
<Div>
<Asp: UpdatePanel ID = "UpdatePanel1" runat = "server" UpdateMode = "Conditional">
<ContentTemplate>
<Asp: ScriptManager ID = "ScriptManager1" runat = "server">
</Asp: ScriptManager>
<Asp: Button ID = "Button1" runat = "server" OnClick = "button#click" Text = "Button"/>
<Asp: FileUpload ID = "File1" runat = "server" Width = "200px"/>
</ContentTemplate>
<Triggers>
<Asp: PostBackTrigger ControlID = "Button1"/>
</Triggers>
</Asp: UpdatePanel>
<Asp: Image id = "image1" ImageUrl = "http://images.cnblogs.com/nopic.gif" Height = "115px" Width = "pixel PX" runat = "server"/>
</Div>
</Form>
</Body>
</Html>

2) Background
Copy codeThe Code is as follows:
Using System;
Using System. Collections. Generic;
Using System. Linq;
Using System. Web;
Using System. Web. UI;
Using System. Web. UI. WebControls;
Using System. IO;
Using System. Data. SqlClient;
Using System. Data;
Public partial class _ Default: baseClass
{
Protected void Page_Load (object sender, EventArgs e)
{
}
Protected void button#click (object sender, EventArgs e)
{
HttpPostedFile upFile = File1.PostedFile;
Int iFileLength = upFile. ContentLength;
Try
{
If (iFileLength = 0)
{
MessageBox ("select the file to upload! ");
}
Else
{
Byte [] FileByteArray = new Byte [iFileLength];
Stream StreamObject = upFile. InputStream;
StreamObject. Read (FileByteArray, 0, iFileLength );
SqlConnection conn = new SqlConnection ("server = ..; database = Test; uid = sa; pwd = 1234 ;");
ExecuteBySQLNonQuery ("delete from imageTable ");
SqlCommand cmd = new SqlCommand ("insert into [imageTable] values (@ image)", conn );
Cmd. Parameters. Add ("@ Image", SqlDbType. Binary, iFileLength). Value = FileByteArray;
Conn. Open ();
Cmd. ExecuteNonQuery ();
Conn. Close ();
MessageBox ("the photo has been uploaded successfully! ");
}
Image1.ImageUrl = "displayempphoto. ashx ";
}
Catch (Exception ex)
{
MessageBox (ex. Message );
}
}
}

3) create displayempphoto. ashx
Copy codeThe Code is as follows:
<% @ WebHandler Language = "C #" Class = "DisplayEmpPhoto" %>
Using System;
Using System. Web;
Using System. Data. SqlClient;
Using System. Web. Configuration;
Using System. Data;
Public class DisplayEmpPhoto: IHttpHandler
{
Public void ProcessRequest (HttpContext context)
{
Using (SqlConnection cn = new SqlConnection (WebConfigurationManager. ConnectionStrings ["CONNECTIONSQL"]. ConnectionString ))
{
SqlCommand SQLCmd = cn. CreateCommand ();
SQLCmd. CommandText = "SELECT imagedata FROM imageTable ";
Cn. Open ();
Using (SqlDataReader dr = SQLCmd. ExecuteReader (CommandBehavior. SingleRow ))
{
If (dr. Read ())
{
// Change the output format of the HTTP File Header so that the browser can know that the output file format is a JPEG image file.
Context. Response. ContentType = "Image/JPEG ";
Context. Response. Clear ();
Context. Response. BufferOutput = true;
Context. Response. BinaryWrite (dr. GetSqlBytes (0). Value );
}
}
}
}
Public bool IsReusable
{
Get
{
Return false;
}
}
}

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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