std::array::front

 

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std::array

成员函数 Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

元素的访问 Original: Element access The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

array::at

array::operator[]

array::front

array::back

array::data

迭代器 Original: Iterators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

array::begin array::cbegin

array::end array::cend

array::rbegin array::crbegin

array::rend array::crend

容量 Original: Capacity The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

array::empty

array::size

array::max_size

修饰符 Original: Modifiers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

array::fill

array::swap

非成员函数 Original: Non-member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

get

swap

Helper类 Original: Helper classes The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

tuple_size

tuple_element

 

reference front();		（因为C + +11）
const_reference front() const;		（因为C + +11）

返回的第一个元素在容器中.

Original:

Returns a reference to the first element in the container.

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在一个空容器中调用front是不确定的.....

Original:

Calling front on an empty container is undefined.

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参数

（无）

Original:

(none)

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返回值

参考的第一个元素

Original:

reference to the first element

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复杂性

常数

Original:

Constant

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注释

对于一个容器c，表达c.front()相当于*c.begin().

Original:

For a container c, the expression c.front() is equivalent to *c.begin().

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为例

下面的代码使用front显示的第一个元素的std::array<char>

Original:

The following code uses front to display the first element of a std::array<char>:

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#include <array>
#include <iostream>
 
int main()
{
    std::array<char> letters {'o', 'm', 'g', 'w', 't', 'f'};
 
    if (!letters.empty()) {
        std::cout << "The first character is: " << letters.front() << '\n';
    }
}

Output:

The first character is o

See also

back	access the last element （公共成员函数）