asp to asp.net dbnull error

[amitbadgi]

Hi I am converting an asp to asp.net, i m getting this error in one of
the files,

Operator '=' is not defined for type 'DBNull' and string "Y".
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Operator '=' is not
defined for type 'DBNull' and string "Y".

Source Error:

Line 259:<p>
<%=(rs_eventtype.Fields.Item("description").Value)%></p></td>
Line 260: <td align="center">
Line 261: <% if (rs_eventtype.Fields.Item("alwayson").Value) = "Y"
then %>
Line 262: <em>always on</em>
Line 263: <% else %>


Source File: C:\Documents and
Settings\amit\WebSite1\list_event_type.aspx Line: 261

Stack Trace:

[InvalidCastException: Operator '=' is not defined for type 'DBNull'
and string "Y".]

Microsoft.VisualBasic.CompilerServices.Operators.ConditionalCompareObjectEqual(Object
Left, Object Right, Boolean TextCompare) +135
ASP.list_event_type_aspx.__Render__control1(HtmlTextWriter __w,
Control parameterContainer) in C:\Documents and
Settings\amit\WebSite1\list_event_type.aspx:261
System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer,
ICollection children) +98
System.Web.UI.Control.RenderChildren(HtmlTextWriter writer) +20
System.Web.UI.Page.Render(HtmlTextWriter writer) +27
System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer,
ControlAdapter adapter) +53
System.Web.UI.Control.RenderControl(HtmlTextWriter writer,
ControlAdapter adapter) +280
System.Web.UI.Control.RenderControl(HtmlTextWriter writer) +24
System.Web.UI.Page.ProcessRequestMain(Boolean
includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
+8878

 

[msnews.microsoft.com]

In the query that you are using to retrieve the data from the database, use
an ISNULL (or some other equivalent) to return 'N' (or some other value,
depending on your logic) for NULL values.