ASP.NET Repeater ItemDataBound事件中等效的Eval（“field”）？

I want to do the equivalent of Eval("field") in an ASP.NET repeater ItemDataBound Event but am not sure what to cast e.Item.DataItem as. The data source type could vary as this is reusable code in a custom control. So how can I access a field in e.Item.DataItem by field name (a string)?I want to do the equivalent of Eval("field") in