std::basic_ios<CharT,Traits>::fill

 

C++

语言

标准库头文件

自立与有宿主实现

具名要求

语言支持库

概念库 (C++20)

诊断库

工具库

字符串库

容器库

迭代器库

范围库 (C++20)

算法库

数值库

本地化库

输入/输出库

文件系统库 (C++17)

正则表达式库 (C++11)

原子操作库 (C++11)

线程支持库 (C++11)

技术规范

 

输入/输出库

I/O 操纵符

C 风格 I/O

缓冲

basic_streambuf

basic_filebuf

basic_stringbuf

basic_spanbuf (C++23)

strstreambuf (C++98 中弃用)

basic_syncbuf (C++20)

流

抽象

ios_base

basic_ios

basic_istream

basic_ostream

basic_iostream

文件 I/O

basic_ifstream

basic_ofstream

basic_fstream

字符串 I/O

basic_istringstream

basic_ostringstream

basic_stringstream

数组 I/O

basic_ispanstream (C++23)

basic_ospanstream (C++23)

basic_spanstream (C++23)

istrstream (C++98 中弃用)

ostrstream (C++98 中弃用)

strstream (C++98 中弃用)

同步的输出

basic_osyncstream (C++20)

类型

streamoff

streamsize

fpos

错误类别接口

iostream_category (C++11)

io_errc (C++11)

 

std::basic_ios

成员函数

basic_ios::basic_ios

basic_ios::~basic_ios

状态函数

basic_ios::good

basic_ios::eof

basic_ios::fail

basic_ios::bad

basic_ios::operator!

basic_ios::operator bool

basic_ios::rdstate

basic_ios::setstate

basic_ios::clear

格式化

basic_ios::copyfmt

basic_ios::fill

杂项

basic_ios::exceptions

basic_ios::imbue

basic_ios::rdbuf

basic_ios::tie

basic_ios::narrow

basic_ios::widen

受保护成员函数

basic_ios::init

basic_ios::move (C++11)

basic_ios::swap (C++11)

basic_ios::set_rdbuf (C++11)

 

CharT fill() const;	(1)
CharT fill( CharT ch );	(2)

管理用于填充输入转换到指定宽度的填充字符。

1) 返回当前的填充字符

2) 设置填充字符为 ch ，返回填充字符的先前值

参数

ch

-

用作填充字符的字符

返回值

调用函数前的填充字符。

示例

运行此代码

#include <iostream>
#include <iomanip>
 
int main ()
{
  std::cout << "With default setting : " << std::setw(10) << 40 << '\n';
  char prev = std::cout.fill('x');
  std::cout << "Replaced '" << prev << "' with '"
            << std::cout.fill() << "': " << std::setw(10) << 40 << '\n';
}

输出：

With default setting :         40
Replaced ' ' with 'x': xxxxxxxx40

参阅

setfill

更改填充字符 (函数模板)