cannot display image in image control - asp.net

Question

Its my handler (.ashx)
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else Throw New ArgumentException("No parameter specified") End If
Dim imageData() As Byte = {}
' get the image data from the database using the employeeId Querystring context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(imageData)
Everything is working fine.Only the imageData length is 0 so the image is unable to display.
#Sean: its elsewhr.. here the querystring correctly takes the employeeid passed...
heres the code for db access:
Public Sub bind()
Dim ds1 As New DataSet()
Dim con As New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("ConnectionString").ToString)
con.Open()
Dim query As String = "select * from EmployeeTable"
Dim cmd As New SqlCommand()
Dim da1 As New SqlDataAdapter(query, con)
da1.Fill(ds1, "EmployeeTable")
GridView1.DataSource = ds1.Tables("EmployeeTable")
GridView1.DataBind()
con.Close()
End Sub

Answer 1

You're loading a load of data into the GridView but nothing is being loaded into your imageData variable. So we'll just connect to the database and pull that data out. I'm assuming your image column is called imageData but please change as appropriate.
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then
EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else
Throw New ArgumentException("No parameter specified")
End If
Dim imageData() As Byte = {}
' get the image data from the database using the employeeId Querystring
Using con As New SqlConnection(ConfigurationManager.AppSettings("ConnectionString"))
Using cmd As New SqlCommand("SELECT imageData FROM EmployeeTable WHERE EmployeeID = #EmployeeID", con) 'select imageData column, change column name as appropriate
cmd.Parameters.AddWithValue("#EmployeeID", EmployeeID)
Try
con.Open()
Using rdr As SqlDataReader = cmd.ExecuteReader()
If rdr.Read() Then
imageData = CType(rdr("imageData"), Byte()) 'convert imageData column from result set to byte array and assign to variable
End If
End Using
Catch ex As Exception
'do any error handling here
End Try
End Using
End Using
context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(imageData)

Answer 2

Changed the code in the handler to this:
Sub ProcessRequest(ByVal context As HttpContext) Implements IHttpHandler.ProcessRequest
Dim EmployeeID As Integer
If (Not (context.Request.QueryString("EmployeeID")) Is Nothing) Then
EmployeeID = Convert.ToInt32(context.Request.QueryString("EmployeeID"))
Else
Throw New ArgumentException("No parameter specified")
End If
Dim Image() As Byte = {}
' get the image data from the database using the employeeId Querystring
Dim con As New SqlConnection(System.Configuration.ConfigurationManager.AppSettings("ConnectionString").ToString)
Dim cmd As New SqlCommand("SELECT Image FROM EmployeeTable WHERE EmployeeID = #EmployeeID", con)
'select imageData column, change column name as appropriate
cmd.Parameters.AddWithValue("#EmployeeID", EmployeeID)
Try
con.Open()
Dim rdr As SqlDataReader = cmd.ExecuteReader()
While rdr.Read()
Image = CType(rdr("Image"), Byte())
'convert imageData column from result set to byte array and assign to variable
End While
Catch ex As Exception
'do any error handling here
End Try
context.Response.ContentType = "image/jpeg"
context.Response.BinaryWrite(Image)
End Sub
Worked for me, may be it will work for you too...