c# - Binding DataGridView to database with EF5 classes not sending changes to database -

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i using entity framework 5.0 + .net 4.5

i have created database using ef model first approach , want bind datagridview database using ef classes changes database or in datagridview synchronized automatically.

this code:

//form level fields private bindinglist<product> _products; private bindingsource _productsource = new bindingsource();   ... in form load event //load data database using ef classes var tmp = _context.basecategoryset.oftype<product>().tolist();  //converting ibindinglist _products = new bindinglist<product>(tmp); _products.allowedit = true; _products.allownew = true;  _productsource.datasource = _products;   //setting gridcontrol's data source productgrid.datasource = _productsource;

i can add new rows or change data, changes not sent database - missing?

additional things did in hope find solution...

1) added save button call updating grid control's data database explicitly, code:

_productsource.endedit(); _context.savechanges();

->this did not result in storing new record database

2) added code add new records bunch of controls individual record properties (textboxes, datepickers)

var x = _context.basecategoryset.create<product>(); //settting x properties values //that set in aforementioned individual controls  _context.basecategoryset.add(x); _context.savechanges();

-->when add new records using technique - stored in database, once more strange behavior - new record not automatically loaded in grid control (but should be, since databinding grid corresponding ef dbset...)

and 1 more strangeness - updates have made in datagridview control records loaded database - updates sent database...

3) switched devexpress xtragrid stadard datagridview control, did not help...

i have searched through tons of topics regarding ef databinding no success...

don't know if matters, using inheritance in entity model: product derives unifofsales , unitofsales derives basecategory class.

one more thing tried

i tried (..).local.tobindinglist suggested ladislav mrnka in post how make 2 way-databinding using ef in winforms?

well did send changes database, changes stored in base class table (basecategory), there table derived class well. code used binding

_context.basecategoryset.oftype<product>.load();  //i tried use derived class oftype<product> ensure compiler //knows instance of derived class (product),  //not base class basecategory,  //but can not "local" working oftype... productgridview.datasource = _context.basecategoryset.local.tobindinglist();

i did find solution!

i had add dbset products in dbcontext class ef model derived class (product, derived basecategory class)

after use 

productgridview.datasource=_context.products.local.tobindinglist();

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