命令模式#
命令就是面向对象化的回调。
示例代码
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65#include <iostream>
#include <vector>
#include <string>
using namespace std;
//基类
class Command
{
public:
virtual void execute() = 0;
virtual ~Command(){}
};
class ConcreteCommand1 : public Command
{
string arg;
public:
ConcreteCommand1(const string & a) : arg(a) {}
void execute() override
{
cout<< "#1 process..."<<arg<<endl;
}
};
class ConcreteCommand2 : public Command
{
string arg;
public:
ConcreteCommand2(const string & a) : arg(a) {}
void execute() override
{
cout<< "#2 process..."<<arg<<endl;
}
};
class MacroCommand : public Command
{
vector<Command*> commands;
public:
void addCommand(Command *c) { commands.push_back(c); }
void execute() override
{
for (auto &c : commands)
{
c->execute();
}
}
};
int main()
{
ConcreteCommand1 command1(receiver, "Arg ###");
ConcreteCommand2 command2(receiver, "Arg $$$");
MacroCommand macro;
macro.addCommand(&command1);
macro.addCommand(&command2);
macro.execute();
}
命令模式很容易实现撤销和重做