How to group by in entity framework? RSS

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  rrasheli

  Member

  18 Points

  31 Posts

  How to group by in entity framework?

  Dec 14, 2012 08:28 AM|LINK

  Hi

  I have this Columns in my database table.

  OrderId     ProductName     InvoiceNo     Price

  1               mouse               15425           12 $

  2               keyboard           14524           14 $

  3               modem              15425           34 $

  In this table two record have same InvoiceNo. I want to group by InvoiceNo by entity framwork and show that data in gridview asp.net.

  My code is here:

  private void BindGridView()
  {
      using (var db = new Context())
      {
          var dt = db.Orders.ToList();
          myGrid.DataSource = db.Orders.ToList();
          myGrid.DataBind();
      }
  }

  I used db.Orders.ToList().GroupBy(x => x.InvoiceNo); and db.Orders.GroupBy(x => x.InvoiceNo).ToList(); but I get error.

  Please help me!

  Thanks

  Is never too late to start×
  • Edited by rrasheli on Dec 14, 2012 08:30 AM
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  gregaDro

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  65 Posts

  Re: How to group by in entity framework?

  Dec 14, 2012 09:41 AM|LINK

  var dt = from o in db.Orders
           group o by o.InvoiceNo into ord
           select new { OrderId = ord.OrderId, ProductName = ord.ProductName, InvocieNo = ord.InvocieNo, Price = ord.Price };
  			 
  myGrid.DataSource = dt.ToList();
  myGrid.DataBind();

  • Edited by gregaDro on Dec 14, 2012 09:41 AM
  • Edited by gregaDro on Dec 14, 2012 09:43 AM
  • Edited by gregaDro on Dec 14, 2012 09:55 AM
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  rrasheli

  Member

  18 Points

  31 Posts

  Re: How to group by in entity framework?

  Dec 14, 2012 11:23 AM|LINK

  But in this line has error and unknow ProductName , InvoiceNo , Price.

  select new { OrderId = ord.OrderId, ProductName = ord.ProductName, InvocieNo = ord.InvocieNo, Price = ord.Price };

  
  
  

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  RameshRajend...

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  Re: How to group by in entity framework?

  Dec 14, 2012 11:36 AM|LINK

  Hai

  Try this 

  var dt = (from x in db.Orders group x by x.InvoiceNo).ToList();

  • Edited by RameshRajendran on Dec 14, 2012 11:37 AM
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  rrasheli

  Member

  18 Points

  31 Posts

  Re: How to group by in entity framework?

  Dec 14, 2012 11:52 AM|LINK

  After bind gridview to 'dt' I get this error

  DataBinding: 'System.Data.Objects.ELinq.InitializerMetadata+Grouping`2[[System.Int32, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[DomainClasses.Order, DomainClasses, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]' does not contain a property with the name 'OrderId

  OrderId is myGrid DataKeyNames.

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  Decker Dong ...

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  Re: How to group by in entity framework?

  Dec 15, 2012 12:47 AM|LINK

  rrasheli

  I used db.Orders.ToList().GroupBy(x => x.InvoiceNo); and db.Orders.GroupBy(x => x.InvoiceNo).ToList(); but I get error.

  Hi,

  In LINQ, Group by is different from that of SQL. So if you wanna do group by, you can just use SQL's group by and import this into EntityFramework having a try.

  • Marked as answer by decker dong - msft on Dec 20, 2012 12:02 AM