how to display an image from database? - asp.net

Question

i know too that this (kind of) question has been asked and answered many times. I myself have asked this once before. But I havnt been successful yet. how do I display the image in an image control for a particular employee ID... Heres my code:
`
bind()
GridView1.Visible = "True"
Dim strQuery As String = "SELECT Image FROM EmployeeTable WHERE EmployeeID =#EmployeeID"
Dim cmd As SqlCommand = New SqlCommand(strQuery)
cmd.Parameters.Add("#EmployeeID", SqlDbType.Int).Value() = Convert.ToInt32(Request.QueryString("ImageID"))
Dim dt As DataTable = GetData(cmd)
If dt IsNot Nothing Then
**Dim bytes() As Byte = CType(dt.Rows(1)("Image"), Byte())**
Response.Buffer = True
Response.Charset = ""
Response.Cache.SetCacheability(HttpCacheability.NoCache)
Response.ContentType = dt.Rows(0)("ContentType").ToString()
Response.AddHeader("content-disposition", "attachment;filename=" + dt.Rows(1)("Name").ToString())
Response.BinaryWrite(bytes)
Response.Flush()
Response.End()
End If`
Getting error at the line in bold. "There is no row at position 1"...
Actually I want to fetch (display) the image for a particular employee id. How does it concern a row position? I dont know why i have written that line of code. Anyway, I know there are guys who can help me with this and so I thank them in advance...
OK, Heres my code for adding the image to the database. This is working fine.
Dim imageData As Byte() = New Byte(FileUpload1.FileContent.Length) {}
FileUpload1.FileContent.Read(imageData, 0, Convert.ToInt32(FileUpload1.FileContent.Length))
Dim con As New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("ConnectionString").ToString)
con.Open()
If EmployeeIDTextBox.Text = "" Then
MsgBox("Please Enter EmployeeID to Add Photo")
Else
Dim com As New SqlCommand("UPDATE EmployeeTable SET IMAGE = #IM where EmployeeID='" & EmployeeIDTextBox.Text & "'", con)
Dim filePath As String = Server.MapPath(FileUpload1.FileName)
'Dim imageData As Byte() = File.ReadAllBytes(filePath)
com.Parameters.AddWithValue("#IM", imageData)
com.ExecuteNonQuery()
MsgBox("File Saved Successfully!")
End If
End Sub
And now this is my code for retrieving & displaying the same image in an image control...
bind()
GridView1.Visible = "True"
'If Request.QueryString("ImageID") IsNot Nothing Then
Dim strQuery As String = "SELECT Image FROM EmployeeTable WHERE EmployeeID =#EmployeeID"
Dim cmd As SqlCommand = New SqlCommand(strQuery)
cmd.Parameters.Add("#EmployeeID", SqlDbType.Int).Value() = Convert.ToInt32(Request.QueryString("Image"))
Dim dt As DataTable = GetData(cmd)
If dt IsNot Nothing Then
Dim bytes() As Byte = CType(dt.Rows(0)("Image"), Byte())
Response.Buffer = True
Response.Charset = ""
Response.Cache.SetCacheability(HttpCacheability.NoCache)
Response.ContentType = dt.Rows(0)("ContentType").ToString()
Response.AddHeader("content-disposition", "attachment;filename=" + dt.Rows(1)("Name").ToString())
Response.BinaryWrite(bytes)
Response.Flush()
Response.End()
End IF
This is not working...

Answer 1

Array indexes start from 0
Use
Dim bytes() As Byte = CType(dt.Rows(0)("Image"), Byte())
How is it that you don't know why you have written that?
The code you have will prompt a user to save the image file on his pc.
It will not show the image in an image control.

Answer 2

U can use a Http Handler and use the below code in ProcessRequest()
int Id = Convert.ToInt32(Request.QueryString["ImgId"]);
using (var conn = new SqlConnection(connectionString))
using (var command = new SqlCommand(
"SELECT ImageFile FROM ImageTable WHERE ImageId = #ImgId", conn))
{
command.Parameters.Add("#ImgId", SqlDbType.Int).Value = Id ;
conn.Open();
Response.ContentType = "image/gif"; //u can set it per ur requirement
Response.BinaryWrite((byte[]) command.ExecuteScalar());
}
and then use image in your page as :
<asp:Image id="Img_Db" runat="server" ImageUrl="Image.ashx?ImgId=1"/>