德尔福 基础

并行

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Using_TParallel.For_from_the_Parallel_Programming_Library

Using TParallel.For from the Parallel Programming Library

 

Go Up to Using the Parallel Programming Library

The Parallel Programming Library (PPL) includes a loop function, TParallel.For, that allows to run its loops in parallel.

Within parallel loops, you must transform your operations into thread-safe operations. You can use members of the System.SyncObjs unit, such as TInterlocked methods.

Converting a For Loop into a TParallel.For Loop

Delphi:

For Loop	TParallel.For Loop
for I := 1 to 10 do begin // … end;	TParallel.For(1, 10, procedure(I: Integer) begin // … end);

C++:

If you are using a Clang-enhanced C++ compiler, you can use lambda expressions:

For Loop	TParallel.For Loop
for (int i = 1; i <= 10; i++) { // … }	TParallel::For(0, 10, TProc1<int>([](int I){ // … }));

You can alternatively use a functor, which works with both previous-generation compilers and Clang-enhanced compilers:

For Loop	TParallel.For Loop
for (int i = 1; i <= 10; i++) { // (Loop logic) }	class TMyFunctor : public TCppInterfacedObject<TProc__1<int> > { public: void __fastcall Invoke(int I) { // (Loop logic) } }; // … TParallel::For(1, 10, System::DelphiInterface<TProc__1<int> >(new TMyFunctor()));

If the loop needs access to one or more variables from the context outside the callback function, you must use a functor as follows:

1. Declare variables in the functor class to hold copies or references to the variables that you need.
2. Declare a constructor of the functor class that accepts the copies or references to those variables as parameters and initializes the corresponding functor variables with their values.
3. Pass those variables to the contructor when you instantiate the functor.
4. In your logic, in Invoke(), you can access those functor variables.

For example:

class TMyFunctor : public TCppInterfacedObject<TProc__1<int> > {
public:
  TMyFunctor(int a, TB *b) : a(a), b(b) {}
  void __fastcall Invoke(int I) {
    // (Loop logic)
  }
  int a;
  TB *b;
};

// …

TParallel::For(1, 10, System::DelphiInterface<TProc__1<int> >(new TMyFunctor(a, b)));

分类方法

 TTest = class;
 
 // Declaring metaclass type
 TTestClass = class of TTest;
 
 TTest = class
 public
   // Class methods
   class function add(I, J: Integer): Integer;
   class function GetClsName: string;
 
   // Virtual class method
   class function GetClsNameVirt: string; virtual;
 
   // Class getter and setter
   class function GetCount: Integer;
   class procedure SetCount(I: Integer);
 
   // Virtual class getter and setter
   class function GetStrProp: string; virtual;
   class procedure SetStrProp(N: string); virtual;
 
   // Class static
   class function GetStaticCount: Integer; static;
   class procedure SetStaticCount(I: Integer); static;
 
   // Class properties
   property Count: Integer read GetCount write SetCount; // Non-virtual
   property StrProp: string read GetStrProp write SetStrProp; // Virtual g/setters
 end;
 
 // Function that takes a class reference
 function RegisterTestType(Cls: TTestClass): boolean;

基本句法元素（Delphi）

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Fundamental_Syntactic_Elements_(Delphi)

程序和功能（德尔福）

 

 http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Procedures_and_Functions_(Delphi)

表达式（德尔福）

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Expressions_(Delphi)

编译器属性  volatile

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Compiler_Attributes#Volatile

 

System.TimeSpan.TTimeSpan

 http://docwiki.embarcadero.com/Libraries/Tokyo/en/System.TimeSpan.TTimeSpan

使用并行编程库

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Using_the_Parallel_Programming_Library

简单类型（Delphi）

http://docwiki.embarcadero.com/RADStudio/Tokyo/en/Simple_Types_(Delphi)