"is" operator doesn't evaluate correctly while performing databind

[Alistair Lacy]

Hi

Ive got a custom collection of class which I use as the data source for a
DataGrid control.

I execute the following code prior to beginning my data binding:

if (list_[0] is BatchWorkItem) { ....} // do stuff

This evaluates to true.

I then execute the DataBind() method for the datagrid. In my handler for
ItemDataBound. Within the event handler I execute the same code, however this
time is evaluates to false.

After the DataBinding is complete, I again execute that expression and it
evalutes to true.

During this time I don't perform any operations of the datasource, nor the
contents.

The full code listing is as follow:

In Page Load (Not post back condition)

if (listSource_[0] is BatchWorkListItem) {
// compiler steps in
}

// populate the data grid.
populateGrid();

if (listSource_[0] is BatchWorkListItem) {
// compiler steps in
}

The following are the handler method(s)

private void populateGrid() {
workListGrid.DataSource = listSource_;
workListGrid.DataKeyField = "ID"; // Property of BatchWorkListItem
workListGrid.DataBind();
}

private void workListGrid_ItemDataBound(object sender,
System.Web.UI.WebControls.DataGridItemEventArgs e) {
// check what type and activity the work list items is for the
// navigation URL

switch (e.Item.ItemType) {
case ListItemType.AlternatingItem :
// force a fall-through.
goto case ListItemType.Item;
case ListItemType.Item :
resolveProceedUrl(e.Item.ItemIndex);
break;
}
}

private void resolveProceedUrl(int index) {
// hard coded index for debugging purpose
if (listSource_[0] is BatchWorkListItem) {
// compiler doesn't step in here
}
}

When I add watches to the datasource, I don't see any changes on the
contents during the binding process.

Thanks in advance for the assistance..