二进制流上传图片，预览，读取显示

<div>
<asp:FileUpload ID="FileUpload1" runat="server" CssClass="btn" Width="320px" onchange="getValue()" /> <asp:Button ID="btnAdd" runat="server" Text="Submit" ValidationGroup="AddPlat" CssClass="btn" Width="80px" OnClick="btnAdd_Click" />
<div id="t2" runat="server" style="width: 150px; height: 120px; visibility: hidden; display: none; border: solid 1px #CCC;">
<img alt="" id="t1" runat="server" src="" style="width: 150px; height: 120px; border: solid 1px #CCC; display: none;" />
</div>
<asp:Image ID="imageSony" runat="server" BorderStyle="Solid" Width="150px" Height="120px" ImageUrl="" />
</div>

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string imageid = "1";
if (Request.QueryString["itemid"] != null)
{
imageid = Request.QueryString["itemid"].ToString();
}
int imgID = Int32.Parse(imageid);
ShowImage(imgID);
}
}

private void ShowImage(int itemID)
{
DataTable dt = new DataTable();
dt = srb.GetSonyItem(itemID);//获得数据源
byte[] b_image = (byte[])dt.Rows[0]["Picture"];//得到数据库二进制字段内容
if (b_image.Length > 0)
{
Byte[] byteImg = (byte[])dt.Rows[0]["Picture"];
Response.BinaryWrite(byteImg);//写入二进制流
Response.End();
}
}