Don't think VB.NET was C#'s afterthought? You should [ms-help URL].

The DataGridTextBoxColumn class derives from the abstract (MustInherit in Visual Basic) class DataGridColumnStyle. At run time, the DataGridTextBoxColumn hosts a DataGridTextBox control that allows users to edit text.

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[Visual Basic] Note The following types are not fully supported by Visual Basic: DateTime, UInt16, UInt32, UInt64, and TimeSpan. (Operators are not allowed.)