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C++11提供std::array 是封装固定大小数组的容器，与数组相比，它提供很多操作函数，例如：at, [], front, back, data, fill, swap等等，

下面是这些函数的使用示例：

#include 
   
    #include 
    
     #include 
     
      using namespace std;void GetElement(){    const int count = 5;//214748    cout << "init nArray   ";    array
      
        nArray = {23, 87, 34, 57, 12};//初始化    for(int &c: nArray)    {        cout << c << "\t";    }    cout << endl;    nArray.fill(9);//以9填充容器所有内容    cout << "nArray.fill(9) ";    for(int &c: nArray)    {        cout << c << "\t";    }    cout << endl;    //double startTime1 = clock();//1计算开始    for(int i = 0; i < count; i++)//214748    {        nArray[i] = (i + 1) * 10;    }    for(int &c: nArray)    {        cout << c << "\t";    }    cout << endl;    //double endTime1 = clock();//1时间结束    cout << "nArray.size = " << nArray.size() << " nArray.isEmpty = " << nArray.empty()         << "  nArray.max_size = " << nArray.max_size() << endl;    //cout << "for    1 run time is: " << (double)(endTime1 - startTime1) / CLOCKS_PER_SEC << "s" << endl;    cout << endl;    array
       
         nArray2;//nArray2的元素个数count必须和nArray一样，则否下面的赋值会报错    nArray2 = nArray;    for(int &c: nArray2)    {        cout << c << "\t";    }    cout << endl;    cout << "nArray.front = " << nArray.front() << endl;    cout << "nArray[1] ==== " << nArray[1] << endl;    cout << "nArray.at(2) = " << nArray.at(2) << endl;    cout << "nArray.data == " << *(nArray.data()) << endl;    cout << "nArray.back == " << nArray.back() << endl;    cout << endl;    array
        
          nArray3 = {21, 35, 98}; array
         
           nArray4 = {32, 17, 57}; cout << "nArray3 = "; for(int &c: nArray3) { cout << c << "\t"; } cout << endl; cout << "nArray4 = "; for(int &c: nArray4) { cout << c << "\t"; } cout << endl; auto it1 = nArray3.begin(); auto it2 = nArray4.begin(); int &ref1 = nArray3.front(); int &ref2 = nArray4.front(); cout << "*it1 = " << *it1 << " *it2 = " << *it2 << " ref1 = " << ref1 << " ref2 = " << ref2 << endl; cout << "nArray3.data = " << nArray3.data() << " nArray4.data = " << nArray4.data() << endl; cout << "nArray3 swap nArray4 " << endl; //nArray3与nArray4的元素类型和个数必须要一样才能交换，这与vector的swap不一样。 nArray3.swap(nArray4); cout << "nArray3 = "; for(int &c: nArray3) { cout << c << "\t"; } cout << endl; cout << "nArray4 = "; for(int &c: nArray4) { cout << c << "\t"; } cout << endl; cout << "*it1 = " << *it1 << " *it2 = " << *it2 << " ref1 = " << ref1 << " ref2 = " << ref2 << endl; cout << "nArray3.data = " << nArray3.data() << " nArray4.data = " << nArray4.data() << endl; cout << endl;}int main(){ GetElement(); cout << endl; cout << "Hello world" << endl; return 0;}
         
        
       
      
     
    
   

运行结果：

array的赋值必须是类型和元素个数一样，例如nArray3与nArray4类型和个数一样才可以正常使用，这点与vector不同，vector的个数不一样的容器也可以赋值 。

同时使用swap里，两个array的类型和元素个数也样一样。从以上结果看出，swap交换的是内容的值，array的首地址没有变化，迭代器和引用都变了，这与vector不同。

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