Linq - 1

var names = new[] { "Tom", "Dick", "Harry", "Mary", "Jay" }.AsQueryable();

var query =
    from n in names
    where n.Length > 3
    let u = n.ToUpper() //引入新的变量同时保留原来的
    where u.EndsWith ("Y") && n.StartsWith("M")
    select u;

 

names.Where ((n, i) => i % 2 == 0).Dump ("Skipping every second element");

 

    from n in names
    where n.Length == names.Min (n2 => n2.Length)
    select n

 

    from c in Customers
    where c.Purchases.Any (p => p.Price > 1000)
    select c

 

from c in Customers
let highValuePurchases = c.Purchases.Where (p => p.Price > 1000)
where highValuePurchases.Any()
select new
{
    c.Name,
    highValuePurchases
}

Published by Wiz