狠狠色丁香婷婷综合尤物/久久精品综合一区二区三区/中国有色金属学报/国产日韩欧美在线观看 - 国产一区二区三区四区五区tv

前言

本文來告訴大家在C#很少有人會發(fā)現(xiàn)的科技。即使是工作了好多年的老司機(jī)也不一定會知道這些科技，如果覺得我是在騙你，那么請看看本文的內(nèi)容。

原本最初 C# 的設(shè)計是簡單和高效開發(fā)的，在經(jīng)過了這么多年眾多公司和開發(fā)者的努力下，整個 C# 里面包含了大量有趣的功能。其中一部分功能是針對于某些特殊需求設(shè)計的，例如高性能或高并發(fā)或無內(nèi)存回收等。在經(jīng)過了 10 多年的迭代，很少人能完全了解整個 C# 語言和框架級做了哪些有趣的功能。

在網(wǎng)上找了很多大神的博客，然后和很多大神聊天，知道了一些科技，于是就在本文和大家分享一下。如果大家有了解本博客里面沒有收藏的科技，還請告訴我。

現(xiàn)在整個 C# 從編譯器到運(yùn)行時都是開源的，所有權(quán)在 dotnet 基金會上，全部開源的項目都基于最友好的 MIT 協(xié)議和 Apache 2 開源協(xié)議，文檔協(xié)議遵循CC-BY協(xié)議。這將允許任何人任何組織和企業(yè)任意處置，包括使用，復(fù)制，修改，合并，發(fā)表，分發(fā)，再授權(quán)，或者銷售。唯一的限制是，軟件中必須包含上述版 權(quán)和許可提示，后者協(xié)議將會除了為用戶提供版權(quán)許可之外，還有專利許可，并且授權(quán)是免費(fèi)，無排他性的(任何個人和企業(yè)都能獲得授權(quán))并且永久不可撤銷，用戶使用.NET 和 C# 完全不用擔(dān)心收費(fèi)問題和版權(quán)問題，以及后續(xù)無法維護(hù)問題。而 dotnet 基金會是一個開放的平臺，我也是 dotnet 基金會的成員之一。微軟在 2020 的時候依然是 dotnet 基金會最大的支持組織

現(xiàn)在最火的 dotnet 倉庫是 dotnet csharplang 倉庫，當(dāng)前的 C# 語言特性由整個社區(qū)決定，這是一個官方開放用來討論 C# 語言未來的倉庫，天天都有大佬們在討論語言的特性，歡迎大家加入。

接下來讓我告訴大家一些很少有人會發(fā)現(xiàn)的科技

1、無限級判斷空

在 C# 6.0 可以使用??判斷空，那么就可以使用下面代碼

var  v1  =  "123";
string  v2  =  null;
string  v3  =  null;

var  v  =  v1  ??  v2  ??  v3;

var  n  =  2  +  foo?.N  ??  1;

var  foo  =  new  System.Collections.Generic.Dictionary<System.Collections.Generic.List<System.Collections.Generic.List<string>>,  string>();

using  HvcnrclHnlfk  =  System.Collections.Generic.Dictionary<System.Collections.Generic.List<System.Collections.Generic.List<string>>,string>;

var  foo  =  new  HvcnrclHnlfk();

3、辣么大

Func<string,string,  EventHandler>  foo  =  (x,  y)  =>  (s,  e)  =>
{
        var  button  =  (Button)  s;
        button.Left  =  x;
        button.Top  =  y;
};

Button1.Click  +=  foo(0,  -1);

((a  +  b  +  c)  -  (a  +  c))();

var  webControl  =  new  System.Web.UI.WebControls.Control();
var  formControl  =  new  System.Windows.Forms.Control();

using  web  =  System.Web.UI.WebControls;
using  win  =  System.Windows.Forms;

web::Control  webControl  =  new  web::Control();
win::Control  formControl  =  new  win::Control();

//a.dll
namespace  F
{
  public  class  Foo
  {

  }
}
//b.dll
namespace  F
{
  public  class  Foo
  {
    
  }
}

var  str  =  "kktpqfThiq";
string  foo  =  $@"換行
{str}";

__makeref

__reftype

__refvalue

__arglist

[StructLayout(LayoutKind.Explicit)]
public  class  A
{
        [FieldOffset(0)]
        public  byte  One;

        [FieldOffset(1)]
        public  byte  Two;

        [FieldOffset(2)]
        public  byte  Three;

        [FieldOffset(3)]
        public  byte  Four;

        [FieldOffset(0)]
        public  int  Int32;
}

static  void  Main(string[]  args)
{
        A  a  =  new  A  {  Int32  =  int.MaxValue  };

        Console.WriteLine(a.Int32);
        Console.WriteLine("{0:X}  {1:X}  {2:X}  {3:X}",  a.One,  a.Two,  a.Three,  a.Four);

        a.Four  =  0;
        a.Three  =  0;
        Console.WriteLine(a.Int32);
}

2147483647
FF  FF  FF  7F
65535

public  static  void  Foo(this  IF1  foo)
{
          //實(shí)際上大家也看到是如何定義
}

int*  block  =  stackalloc  int[100];  

public  sealed  clas  Foo
{
        public  Foo  F1()
        {
                Console.WriteLine("進(jìn)入F1");
                return  this;
        }

        [Conditional("DEBUG")]
        public  void  F2()
        {
                Console.WriteLine("F2");
        }
}

static  void  Main(string[]  args)
{
        var  foo  =  new  Foo();
        foo.F1();
        foo.F2();
}

static  void  Main(string[]  args)
{
        var  foo  =  new  Foo();
        foo.F1().F2();
}

var  foo  =  new  Foo(10);

if  (foo)
{
        Console.WriteLine("我的類沒有繼承  bool  ，居然可以這樣寫");
}

public  class  Foo
{
        public  Foo(int  value)
        {
                _count  =  value;
        }

        private  readonly  int  _count;

        public  static  bool  operator  true(Foo  mt)
        {
                return  mt._count  >  0;
        }

        public  static  bool  operator  false(Foo  mt)
        {
                return  mt._count  <  0;
        }
}

class  Foo
{
        public  int  Count  {  get;  set;  }
  
        public  static  string  operator  ==(Foo  f1,  Foo  f2)
        {
                if  (f1?.Count  ==  f2?.Count)
                {
                        return  "lindexi";
                }

                return  "";
        }

        public  static  string  operator  !=(Foo  f1,  Foo  f2)
        {
                return  "";
        }
}

await  "林德熙逗比";

await  "不告訴你";

await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  await  "林德熙逗比";

15、變量名使用中文

public  string  H\u00e5rf?ner()
{
        return  "可以編譯";
}

public  class  ??  :  Exception  {  }
public  static  bool  ??(this  string  value)  =>  string.IsNullOrWhitespace(value);

string  s  =  null;
if  (s.??())  
          throw  new  ??();

16、if this == null

一般看到下面的代碼都覺得是不可能進(jìn)入輸出的

if  (this  ==  null)  Console.WriteLine("this  is  null");

f.Foo();  //如果  f  為空，那么這里就不執(zhí)行

void  Foo()
{
      //  如果  this  為空，怎么可以調(diào)用這個方法
      if  (this  ==  null)  Console.WriteLine("this  is  null");
}

//執(zhí)行的代碼

//不執(zhí)行的代碼

if(true)
{
      //執(zhí)行的代碼
}
else
{
      //不執(zhí)行的代碼  
}

if(this  ==  null)
{
      //執(zhí)行的代碼
}
else
{
      //不執(zhí)行的代碼  
}

Fantastic  fantastic  =  (FantasticInfo)  null;
fantastic.Foo();

public  class  Fantastic
{
        private  Fantastic()
        {
        }

        public  static  implicit  operator  Fantastic(FantasticInfo  value)  =>  new  Fantastic();

        public  void  Foo()
        {
        }
}

public  class  FantasticInfo
{
}

Foo()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()();

delegate  Foo  Foo();  //  定義委托

static  void  Main(string[]  args)
{
        Foo  Foo()  //  定義內(nèi)部方法
        {
                return  Foo;
        }
}

delegate  Fx  Fx(Fx  fx);
  Fx  fx  =  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>
                                fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx  =>  fx;

class  Foo
{
        public  void  KzcSevfio()
        {
        }
}
static  void  Main(string[]  args)
{
        GetMethodName<Foo>(foo  =>  foo.KzcSevfio());
}

private  static  void  GetMethodName<T>(Expression<Action<T>>  action)  where  T  :  class
{
        if  (action.Body  is  MethodCallExpression  expression)
        {
                Console.WriteLine(expression.Method.Name);
        }
}

public  sealed  class  Foo
{
        public  int  Count  {  get;  set;  }

        public  override  string  ToString()
        {
                return  Count.ToString();
        }
}

[DebuggerDisplay("{DebuggerDisplay}")]
public  sealed  class  Foo
{
        public  int  Count  {  get;  set;  }

        private  string  DebuggerDisplay  =>  $"(count  {Count})";
}

string  format  =  "000;-#;(0)";

string  pos  =  1.ToString(format);          //  001
string  neg  =  (-1).ToString(format);    //  -1
string  zer  =  0.ToString(format);          //  (0)

class  Program
{
        static  void  Main(string[]  args)
        {
                var  foo  =  new  Foo();
                foo.F1();
        }
}

public  sealed  class  Foo
{
        public  void  F1()
        {
                F2();
        }

        void  F2()
        {
                var  stackTrace  =  new  StackTrace();
                var  n  =  stackTrace.FrameCount;
                for  (int  i  =  0;  i  <  n;  i++)
                {
                        Console.WriteLine(stackTrace.GetFrame(i).GetMethod().Name);
                }
        }
}

F2
F1

private  void  F1()
{
        try
        {
                A();
        }
        catch  (Exception  e)
        {
                
        }
}

private  void  A()
{
        try
        {
                throw  new  ArgumentException("lindexi  is  doubi");
        }
        finally
        {
                throw  new  FileNotFoundException("lsj  is  doubi");
        }
}

private  void  F1()
{
        try
        {
                _  =  new  Foo();
        }
        catch
        {
              //  忽略
        }
}
class  Foo
{
        public  Foo()
        {
                throw  new  Exception("lindexi  is  doubi");
        }

        ~Foo()
        {
        }
}

Foo  foo  =  null;
try
{
        foo  =  (Foo)  FormatterServices.GetUninitializedObject(typeof(Foo));
        var  constructorInfo  =  typeof(Foo).GetConstructor(new  Type[0]);
        constructorInfo!.Invoke(foo,  null);
}
catch
{
}

class  Foo
{

}