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// Copyright (c) AlphaSierraPapa for the SharpDevelop Team
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
using System;
using System.Collections.Generic;
using System.Linq;
public class QueryExpressions
{
public class Customer
{
public int CustomerID;
public IEnumerable<QueryExpressions.Order> Orders;
public string Name;
public string Country;
public string City;
}
public class Order
{
public int OrderID;
public DateTime OrderDate;
public QueryExpressions.Customer Customer;
public int CustomerID;
public decimal Total;
public IEnumerable<QueryExpressions.OrderDetail> Details;
}
public class OrderDetail
{
public decimal UnitPrice;
public int Quantity;
}
public IEnumerable<QueryExpressions.Customer> customers;
public IEnumerable<QueryExpressions.Order> orders;
public object MultipleWhere()
{
return from c in this.customers
where c.Orders.Count<QueryExpressions.Order>() > 10
where c.Country == "DE"
select c;
}
public object SelectManyFollowedBySelect()
{
return from c in this.customers
from o in c.Orders
select new
{
c.Name,
o.OrderID,
o.Total
};
}
public object SelectManyFollowedByOrderBy()
{
return from c in this.customers
from o in c.Orders
orderby o.Total descending
select new
{
c.Name,
o.OrderID,
o.Total
};
}
public object MultipleSelectManyFollowedBySelect()
{
return from c in this.customers
from o in c.Orders
from d in o.Details
select new
{
c.Name,
o.OrderID,
d.Quantity
};
}
public object MultipleSelectManyFollowedByLet()
{
return from c in this.customers
from o in c.Orders
from d in o.Details
let x = d.Quantity * d.UnitPrice
select new
{
c.Name,
o.OrderID,
x
};
}
public object FromLetWhereSelect()
{
return from o in this.orders
let t = o.Details.Sum((QueryExpressions.OrderDetail d) => d.UnitPrice * d.Quantity)
where t >= 1000m
select new
{
OrderID = o.OrderID,
Total = t
};
}
public object MultipleLet()
{
return from a in this.customers
let b = a.Country
let c = a.Name
select b + c;
}
public object Join()
{
return from c in this.customers
join o in this.orders on c.CustomerID equals o.CustomerID
select new
{
c.Name,
o.OrderDate,
o.Total
};
}
public object JoinInto()
{
return from c in this.customers
join o in this.orders on c.CustomerID equals o.CustomerID into co
let n = co.Count<QueryExpressions.Order>()
where n >= 10
select new
{
Name = c.Name,
OrderCount = n
};
}
public object OrderBy()
{
return from o in this.orders
orderby o.Customer.Name, o.Total descending
select o;
}
public object GroupBy()
{
return from c in this.customers
group c.Name by c.Country;
}
public object ExplicitType()
{
return from QueryExpressions.Customer c in this.customers
where c.City == "London"
select c;
}
public object QueryContinuation()
{
return from c in this.customers
group c by c.Country into g
select new
{
Country = g.Key,
CustCount = g.Count<QueryExpressions.Customer>()
};
}
}
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