1.通過var關鍵字實現靈活的類型聲明:
class ImplicitlyTypedLocals2
{
static void Main()
{
string[] Words = { "aPPLE", "BlUeBeRrY", "cHeRry" };
// If a query produces a sequence of anonymous types,
// then you must also use var in the foreach statement.
var upperLowerWords =
from w in Words
select new { Upper = w.ToUpper(), Lower = w.ToLower() };
// Execute the query
foreach (var ul in upperLowerWords)
{
Console.WriteLine("Uppercase: {0}, Lowercase: {1}", ul.Upper, ul.Lower);
}
}
}
2.更加靈活的對象構造方式:
private class Cat
{
// Auto-implemented propertIEs
public int Age { get; set; }
public string Name { get; set; }
}
static void MethodA()
{
// Object initializer
Cat cat = new Cat { Age = 10, Name = "Sylvester" };
}
3.集合裝配的特殊方法:
IEnumerable<int> highScoresQuery =
from score in scores
where score > 80
orderby score descending
select score;
4.對已存在的類型定義進行方法擴展:
namespace ExtensionMethods
{
public static class MyExtensions
{
public static int WordCount(this String str)
{
&nbs
p; return str.Split(new char[] { '' '', ''.'', ''?'' }, StringSplitOptions.RemoveEmptyEntrIEs).Length;
}
}
}
using ExtensionMethods;
string s = "Hello Extension Methods";
int i = s.WordCount();
5.隱式集合類型定義:
var v = new { Amount = 108, Message = "Hello" };
var productQuery =
from prod in products
select new { prod.Color, prod.Price };
foreach (var v in productQuery)
{
Console.WriteLine("Color={0}, Price={1}", v.Color, v.Price);
}
6.Lambda語法:
delegate int del(int i);
del myDelegate = x => x * x;
int j = myDelegate(5); //j = 25
7.查詢語法:
class LowNums
{
static void Main()
{
// A simple data source.
int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };
// Create the query.
// lowNums is an IEnumerable<int>
var lowNums = from num in numbers
where num < 5
select num;
// Execute the query.
foreach (int i in lowNums)
{
Console.Write(i + " ");
}
}
}
// Output: 4 1 3 2 0
8.智能簡約的訪問器聲明:
class LightweightCustomer
{
public double TotalPurchases { get; set; }
public string Name { get; private set; } // read-only
public int CustomerID { get; private set; } // read-only
}
LightweightCustomer obj = new LightweightCustomer();
obj.TotalPurchases = 1;
Console.WriteLine(obj.TotalPurchases.ToString());
9.支持借口,類,結構,方法,特性的partial聲明:
partial class Earth : Planet, IRotate { }
partial class Earth : IRevolve { }
[System.SerializableAttribute]
partial class Moon { }
[System.ObsoleteAttribute]
partial class Moon { }
