Why .Net databinding does not support for class field?

1. the property grid does not display fields
2. One of the reasons why data-binding support is limited to properties happens to be the fact that all of data-binding is built around PropertyDescriptors and not on direct reflection. This allows someone to implement ICustomTypeDescriptor to provide a different OM for the purposes of data-binding than the true set of properties present on the CLR type. For example, DataRowView implements ICustomTypeDescriptor to surface its columns as pseudo-properties that are visible to ASP.NET's data-binding infrastructure (such as GridView/DataGrid columns and DataBinder.Eval). Without this, DataRowView would have two properties - DataView and Index (and the second is the only one remotely interesting for data-binding).

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