实现无刷新上传图片

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("成功上传!");
}
image1.ImageUrl = "displayempphoto.ashx";
}
catch (Exception ex)
{
MessageBox(ex.Message);
}
}
}

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，让浏览器理解所输出文件格式为 JPEG。
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;
}
}
}