关于lambda的基础知识，请参考上一篇的地址如下：

http://www.cnblogs.com/davidgu/p/4825625.html

 

我们再举个STL使用Lambda来进行排序的例子，如下：

Person.h

#ifndef _Domain_Models_Person_H_#define _Domain_Models_Person_H_#include 
     
      #include 
      
       #include 
       
        using namespace std;class Person {    friend ostream& operator<< (ostream& s, const Person& p);private:    string fn;    // first name    string ln;    // last name    int age;public:    Person() { }    Person(const string& f, const string& n)        : fn(f), ln(n)     {    }    string firstname() const;    string lastname() const;    int getAge() const;    void setAge(int a);    static bool sortByName(const Person& p1, const Person& p2);    static bool sortByAge(const Person& p1, const Person& p2);    static void sortDequeByName(deque
        
          &persons);    static void sortDequeByAge(deque
         
           &persons);    static void printPersonDeques(deque
          
            persons);};#endif
          
         
        
       
      
     

 

Person.cpp

#include 
     
      #include "Person.h"inline string Person::firstname() const {    return fn;}inline string Person::lastname() const {    return ln;}inline int Person::getAge() const{    return age;}void Person::setAge(int a){    age = a;}/* binary function predicate:* - returns whether a person is less than another person*/bool Person::sortByName(const Person& p1, const Person& p2){    /* a person is less than another person    * - if the last name is less    * - if the last name is equal and the first name is less    */    return p1.lastname()
      
        &persons){    // sort elements    sort(persons.begin(), persons.end(),    // range        Person::sortByName);       // sort criterion}void Person::sortDequeByAge(deque
       
         &persons){    // sort elements    sort(persons.begin(), persons.end(),    // range        Person::sortByAge);       // sort criterion}ostream& operator<< (ostream& s, const Person& p){    s << "[" << p.lastname() << ", " << p.firstname() << ", " << p.getAge() << "]";    return s;}void Person::printPersonDeques(deque
        
          persons){    deque
         
          ::iterator pos;    for (pos = persons.begin(); pos != persons.end(); ++pos)    {        cout << *pos << endl;    }}
         
        
       
      
     

 

LambdaTest.cpp

#include 
     
      #include 
      
       #include 
       
        #include "LambdaTest.h"#include "../../Core/ContainerUtil.h"using namespace std;void LambdaTest::sortByLambda(){    // create some persons    Person p1("nicolai", "josuttis");    Person p2("ulli", "josuttis");    Person p3("anica", "josuttis");    Person p4("lucas", "josuttis");    Person p5("lucas", "otto");    Person p6("lucas", "arm");    Person p7("anica", "holle");    p1.setAge(20);    p2.setAge(30);    p3.setAge(18);    p4.setAge(2);    p5.setAge(22);    p6.setAge(35);    p7.setAge(95);    // insert person into collection coll    deque
        
          coll;    coll.push_back(p1);    coll.push_back(p2);    coll.push_back(p3);    coll.push_back(p4);    coll.push_back(p5);    coll.push_back(p6);    coll.push_back(p7);    cout << "persons before sort:" << endl;    Person::printPersonDeques(coll);    // sort Persons according to lastname (and firstname)    sort(coll.begin(), coll.end(),                // range        [](const Person& p1, const Person& p2) { // sort criterion        return p1.lastname()
        
       
      
     

 

运行结果:

---------------- sortByLambda(): Run Start ----------------

persons before sort:

[josuttis, nicolai, 20]

[josuttis, ulli, 30]

[josuttis, anica, 18]

[josuttis, lucas, 2]

[otto, lucas, 22]

[arm, lucas, 35]

[holle, anica, 95]

persons after sort by name:

[arm, lucas, 35]

[holle, anica, 95]

[josuttis, anica, 18]

[josuttis, lucas, 2]

[josuttis, nicolai, 20]

[josuttis, ulli, 30]

[otto, lucas, 22]

persons after sort by age:

[josuttis, lucas, 2]

[josuttis, anica, 18]

[josuttis, nicolai, 20]

[otto, lucas, 22]

[josuttis, ulli, 30]

[arm, lucas, 35]

[holle, anica, 95]

---------------- sortByLambda(): Run End ----------------