This repository aims to provide a well-documented example of using Entity Framework 6 and LinQ for use in custom user controls for the Climsoft project developed in VisualBasic.NET
Initial tasks
- Develop examples simultaneously for a station selector and an element selector (connecting to db.stations and db.obselement)
Ability to perform following filters:
- equals "67774010"
- IN {"67774010", "67775050"}
- date greater #01/01/2001#
In addition, the ability to provide a extra customised columns from the select (e.g. the concatenation of id and name)
Further tasks
- Switch to stationelement. Only return those stations that can have data for the currently selected element(s), or only those elements available at the currently selected station(s)
NOTES:
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Array vs List
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IQueryable vs IEnumerable, including notes on paging with Take and Skip (see also diagram). Testing that an object implements an interface doesn't guarented that extension methods will be available.
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DataSource vs BindingSource
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Interfaces (vs Duck Typing and ABCs)
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"Unable to convert MySQL date/time value to System.DateTime"
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Replace
Chr(34) &
string concatenation with escaped quotes ("""
), StringBuilder and String.Format. Also check whether using + or & for concatenation.