Retrieving an image from SQL, test for null

I have an employee directory application that displays employees in a gridview. When a record is selected, a new page opens and displays all info about the employee, including their photo. I have the code working that displays the photos, however, when no photo is present an exception is thrown that "Unable to cast object of type System.DbNull to System.Byte[]". I'm not sure how to test for no photo before trying to write it out.

My code is as follows (with no error trapping):

PrivateSub Page_Load(ByVal senderAs System.Object,ByVal eAs System.EventArgs)HandlesMyBase.Load,Me.Load

Dim tempAsString

Dim connPhotoAs System.Data.SqlClient.SqlConnection

Dim connstringAsString

connstring = Web.Configuration.WebConfigurationManager.ConnectionStrings("connPhoto").ConnectionString

connPhoto =New System.Data.SqlClient.SqlConnection(connstring)

temp = Request.QueryString("id")

Dim SqlSelectCommand2As System.Data.SqlClient.SqlCommand

Dim sqlstringAsString

sqlstring ="Select * from dbo.PhotoDir WHERE (CMS_ID = " + temp +")"

SqlSelectCommand2 =New System.Data.SqlClient.SqlCommand(sqlstring, connPhoto)

Try

connPhoto.Open()

Dim myDataReaderAs System.Data.SqlClient.SqlDataReader

myDataReader = SqlSelectCommand2.ExecuteReader

DoWhile (myDataReader.Read())

Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))

Loop

connPhoto.Close()

Catch SQLexecAs System.Data.SqlClient.SqlException

Response.Write("Read Failed : " & SQLexec.ToString())

EndTry

EndSub

EndClass

If you could point me in the right direction I would appreciate it.

lwhalen618:

when no photo is present an exception isthrown that "Unable to cast object of type System.DbNull toSystem.Byte[]

lwhalen618:

DoWhile (myDataReader.Read())

Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))

Loop

did you try to check for nulls ??

DoWhile (myDataReader.Read())
if Not IsDBNull(myDataReader.Item("ImportedPhoto")) then
Response.BinaryWrite(myDataReader.Item("ImportedPhoto"))
End if
Loop

hope it works... pls let me know

Good Luck./.

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I did try testing for null but was doing it incorrectly. Your code worked fine. Thanks!