simple example
1. My example Database stucture is as follows:
[FileId] UNIQUEIDENTIFIER PRIMARY CLUSTERED KEY
[Data] IMAGE NOT NULL
2. ViewImage.aspx.cs code
-- BEGIN CODE --
using System;
using System.Data;
using System.Data.SqlClient;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class ViewImage : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Guid id;
try
{
id = new Guid(Request.QueryString["id"]);
}
catch
{
// display a default image or message
// saying id is invalid
return;
}
this.AttachImageContent(id);
}
/// <summary>
///
/// </summary>
/// <param name="id"></param>
private void AttachImageContent(Guid id)
{
byte[] content = this.GetImageContent(id);
Response.ClearContent();
Response.ContentType = "image/jpg"; // get it from database
Response.OutputStream.Write(content, 0, content.Length);
Response.End();
}
private const string ConnectionString =
"server=(local);uid=;password=;" +
"database=BlobDatabase;pooling=true;max pool size=1;min pool size=1;";
/// <summary>
///
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
private byte[] GetImageContent(Guid id)
{
// should be a stored procedure
string query = "SELECT [Data] FROM [File] WHERE [FileId] = @FileId";
SqlConnection connection = new SqlConnection(ConnectionString);
SqlCommand command = new SqlCommand(query, connection);
SqlParameter parameter = new SqlParameter("@FileId",
SqlDbType.UniqueIdentifier);
parameter.Direction = ParameterDirection.Input;
parameter.Value = id;
command.CommandTimeout = 120;
command.CommandType = CommandType.Text;
command.Parameters.Add(parameter);
try
{
connection.Open();
return (byte[]) command.ExecuteScalar();
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (connection.State != ConnectionState.Closed)
connection.Close();
}
}
}
-- END CODE --
3. Aspx Page html code
-- BEGIN CODE --
<%@ 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>Untitled Page</title>
<style type="text/css">
</style>
</head>
<body>
<form id="form1" runat="server">
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns=False>
<Columns>
<asp:TemplateField>
<ItemTemplate>
<img
src='ViewImage.aspx?id=<%#DataBinder.Eval(Container.DataItem, "FileId")%>'/>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="FirstName"/>
</Columns>
</asp:GridView>
</form>
</body>
</html>
-- END CODE --
4. Apsx behind c# code
-- BEGIN CODE --
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
GridView1.DataSource = GetDataSource();
GridView1.DataBind();
}
private DataTable GetDataSource()
{
DataTable table = new DataTable();
table.Columns.Add("FileId", typeof(string));
table.Columns.Add("FirstName", typeof(string));
DataRow row = table.NewRow();
row[0] = "e8302aa9-e82c-4d20-b3ae-79f8c5009dfb";
row[1] = "George W Bush";
table.Rows.Add(row);
return table;
}
}
-- END CODE --
Hope this helps
--
Milosz Skalecki
MCP, MCAD
CLEAR-RCIC said:
I have several images i want to display in an ASP.Net application. The
images are being passed to me in binary format from another application. Is
there a good way to write them directly to an HMTL page without having to
save them to the server and create a URL to the virtual directory?
FYI: I currently am doing this with just single images. I do a
Response.BinaryWrite(byte) to display the one image. The advantage is that I
never have to worry about deleting the images at some later time.
Unfortunatly, this method does not lend itself to multiple images.
