Advantages of Typed DataTables

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OpenPetra's Typed DataTables provide many advantages over normal, untyped DataTables.

The resulting source code that defines the resulting Typed DataTables is automatically created by a generator (invoked by 'nant generateORM').

List of Advantages of Typed DataTables

  • Typed DataColumns (e.g. Int32, string, DateTime, ...) instead of everything just being of Type object.
    • Relieves the developer from casting all the time. Casting is annoying for the developer and error-prone, and one only finds out at run-time whether the cast to a certain type is correct as one side of the cast is always of Type object and therefore will accept anything at compile-time.
    • Provides compile-time checks for the correct Type when reading data from/writing data to DataColumns.
  • Easier referencing of DataColumns: MyTable.MyColumn instead of MyTable.Columns['MyColumn']
    • When using the MyTable.MyColumn notation: compile-time checks are done if DataColumns are existent/spelled correctly.
    • When using the MyTable.MyColumn notation: The IDE offers Code Completion and shows ToolTips about the Type of a DataColumn when the mouse cursor is 'hovering' over a DataColum name.
    • When using the MyTable.MyColumn notation: Performance increase - the lookup of the Index of the DataColumn is done only once, whereas with a normal DataTable it is done everytime a DataColumn is accessed by name.