Array容器的相关知识，array是一个顺序容器，和其他标准容器相比它的特点是容器的大小固定，顺序存储。
1：array的构造函数
array（）；
array（const array & right）；
2：array的成员变量
Type DefinitionDescription
array::const_iteratorThe type of a constant iterator for the controlled sequence.
array::const_pointerThe type of a constant pointer to an element.
array::const_referenceThe type of a constant reference to an element.
array::const_reverse_iteratorThe type of a constant reverse iterator for the controlled sequence.
array::difference_typeThe type of a signed distance between two elements.
array::iteratorThe type of an iterator for the controlled sequence.
array::pointerThe type of a pointer to an element.
array::referenceThe type of a reference to an element.
array::reverse_iteratorThe type of a reverse iterator for the controlled sequence.
array::size_typeThe type of an unsigned distance between two elements.
array::value_typeThe type of an element.
3：array的关于迭代器的成员函数
Iterators
beginReturn iterator to beginning(public member function )
endReturn iterator to end(public member function )
rbeginReturn reverseiterator to reverse beginning(public member function )
rendReturnreverse iterator to reverse end(public member function )
cbeginReturnconst_iterator to beginning(public member function )
cendReturnconst_iterator to end(public member function )
crbeginReturnconst_reverse_iterator to reverse beginning(public member
function )
crendReturnconst_reverse_iterator to reverse end(public member
function )
这些东西和list中迭代器都类似，在list篇中已经做过大量介绍，这里就不再啰嗦了。
4：array中关于容量的函数
Capacity
sizeReturnsize(public member function )
max_sizeReturnmaximum size(public member function )
emptyTestwhether array is empty(public member function )
4.1 size（）函数的用法，从结果中可以看出array容量的一些端倪来。
size_type size() const;
#include
#include
intmain ()
{
std::array myints;
std::cout <<"size of myints: "<< myints.size() << std::endl;
std::cout <<"sizeof(myints): "<
return0;
}
结果：
size of myints: 5
sizeof(myints): 20
4.2 max_size()函数的用法，说明这个函数和list中的max_size（）的不同
size_type max_size() const;
#include
#include
intmain ()
{
std::array myints;
std::cout <<"size of myints: "<< myints.size() <<'\n';
std::cout <<"max_size of myints: "<< myints.max_size() <<'\n';
return0;
}
结果：
size of myints: 10
max_size of myints: 10
4.3 empty函数
bool empty() const;
5．array中关于元素操作的函数
Element access
operator[]Accesselement(public member function )
atAccesselement(public member function )
frontAccessfirst element(public member function )
backAccesslast element(public member function )
dataGetpointer to data(public member function )
5.1 operator[]操作符
reference operator[](size_type off);
const_reference operator[](size_type off) const;
示例：
#include
#include
intmain ()
{
std::array myarray;
unsignedinti;
for(i=0; i<10; i++) myarray[i]=i;// assign some values:
std::cout <<"myarray contains:";// print content
for(i=0; i<10; i++)
std::cout <<' '<< myarray[i];
std::cout <<'\n';
return0;
}
输出结果：
myarray contains: 0 1 2 3 4 5 6 7 8 9
5.2 at（）函数的用法
reference at(size_type off);
const_reference at(size_type off) const;
用法：
#include
#include
intmain ()
{
std::array myarray;
for(inti=0; i<10; i++)
myarray.at(i) = i+1;// assign some values:
std::cout <<"myarray contains:"// print content:;
for(inti=0; i<10; i++)
std::cout <<' '<< myarray.at(i);
std::cout <<'\n';
return0;
}
输出结果：
myarray contains: 1 2 3 4 5 6 7 8 9 10
5.3 front函数的用法
reference front();
const_reference front() const;
示例：
#include
#include
intmain ()
{
std::array myarray = {2, 16, 77};
std::cout <<"front is: "<< myarray.front() << std::endl;// 2
std::cout <<"back is: "<< myarray.back() << std::endl;// 77
myarray.front() = 100;
std::cout <<"myarray now contains:";
for(int& x : myarray ) std::cout <<' '<< x;
std::cout <<'\n';
return0;
}
结果：
front is: 2
back is: 77
myarray now contains: 100 16 77
5.4 back函数的用法
reference back();
const_reference back() const;
关于例子，在5.3中的例子已经包含了
5.5 data函数的用法
Ty *data();
const Ty *data() const;
返回值指向第一个元素的指针，因为是顺序存储，所以知道了首元素的指针就可以知道所有元素了。
#include
#include
#include
intmain ()
{
constchar* cstr ="Test string";
std::array charray;
std::memcpy (charray.data(),cstr,12);
std::cout << charray.data() <<'\n';
return0;
}
结果：
Test string
6修改元素的函数
Modifiers
fillFill arraywith value(public member function )
swapSwap content(public member function )
6.1 fill函数的用法
void fill(const Type& _Val);
函数将array中所有的元素替换成_val
#include
#include
intmain () {
std::array myarray;
myarray.fill(5);
std::cout <<"myarray contains:";
for(int& x : myarray) { std::cout <<' '<< x; }
std::cout <<'\n';
return0;
}
结果：
myarray contains: 5 5 5 5 5 5
6.2 swap函数的用法
void swap(array& right);
交换两个具有相同长度的array，切记两个array的长度必须一致
例子：
#include
#include
intmain ()
{
std::array first = {10, 20, 30, 40, 50};
std::array second = {11, 22, 33, 44, 55};
first.swap (second);
std::cout <<"first:";
for(int& x : first) std::cout <<' '<< x;
std::cout <<'\n';
std::cout <<"second:";
for(int& x : second) std::cout <<' '<< x;
std::cout <<'\n';
return0;
}
结果：
first contains: 11 22 33 44 55
second contains: 10 20 30 40 50
附加头文件中其他跟array类无关的类以及函数
1：tuple_element类
template
class tuple_element > {
typedef Ty type;
};
这个类就是获取array中第几个元素的值，示例如下：
#include
#include
typedef std::array Myarray;
int main()
{
Myarray c0 = {0, 1, 2, 3};
// display contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
// display first element " 0"
std::tuple_element<0, Myarray>::type val = c0.front();
std::cout << " " << val;
std::cout << std::endl;
return (0);
}
结果：
0 1 2 3
0
2：tuple_size类
template
class tuple_size > {
static const unsigned value = N;
};
这个类就是获取array数组的大小，示例
#include
#include
typedef std::array Myarray;
int main()
{
Myarray c0 = {0, 1, 2, 3};
// display contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
// display size " 4"
std::cout << " " << std::tuple_size::value;
std::cout << std::endl;
return (0);
}
结果：
0 1 2 3
4
3：get函数的用法
template
Ty& get(array& arr);
template
const Ty& get(const array& arr);
这个函数就是返回array[id]的索引，示例
#include
#include
typedef std::array Myarray;
int main()
{
Myarray c0 = {0, 1, 2, 3};
// display contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
// display odd elements " 1 3"
std::cout << " " << std::get<1>(c0);
std::cout << " " << std::get<3>(c0);
std::cout << std::endl;
return (0);
}
结果：
0 1 2 3
1 3
4.swap函数的用法
template
void swap(
array& left,
array& right);
交换两个数组的值，示例
#include
#include
typedef std::array Myarray;
int main()
{
Myarray c0 = {0, 1, 2, 3};
// display contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
Myarray c1 = {4, 5, 6, 7};
c0.swap(c1);
// display swapped contents " 4 5 6 7"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
swap(c0, c1);
// display swapped contents " 0 1 2 3"
for (Myarray::const_iterator it = c0.begin();
it != c0.end(); ++it)
std::cout << " " << *it;
std::cout << std::endl;
return (0);
}
结果：
0 1 2 3
4 5 6 7
0 1 2 3
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