asp.net UpdatePanel实现无刷新上传图片
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2024-03-08 20:52:40
1）前台 复制代码 代码如下: <%@ page language="c#" autoeventwireup="true" codefile="default.asp...
1）前台
<%@ 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="button1_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="108px" runat="server"/>
</div>
</form>
</body>
</html>
2）后台
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 button1_click(object sender, eventargs e)
{
httppostedfile upfile = file1.postedfile;
int ifilelength = upfile.contentlength;
try
{
if (ifilelength == 0)
{
messagebox("请选择要上传的文件！");
}
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("已经成功上传了照片!");
}
image1.imageurl = "displayempphoto.ashx";
}
catch (exception ex)
{
messagebox(ex.message);
}
}
}
3）建立一般处理文件displayempphoto.ashx
<%@ 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())
{
// 改变 http 文件头的输出格式，以便让浏览器知道所输出的文件格式是 jpeg 图文件。
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;
}
}
}
复制代码 代码如下:
<%@ 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="button1_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="108px" runat="server"/>
</div>
</form>
</body>
</html>
2）后台
复制代码 代码如下:
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 button1_click(object sender, eventargs e)
{
httppostedfile upfile = file1.postedfile;
int ifilelength = upfile.contentlength;
try
{
if (ifilelength == 0)
{
messagebox("请选择要上传的文件！");
}
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("已经成功上传了照片!");
}
image1.imageurl = "displayempphoto.ashx";
}
catch (exception ex)
{
messagebox(ex.message);
}
}
}
3）建立一般处理文件displayempphoto.ashx
复制代码 代码如下:
<%@ 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())
{
// 改变 http 文件头的输出格式，以便让浏览器知道所输出的文件格式是 jpeg 图文件。
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;
}
}
}