public member function
<ios> <iostream>

std::basic_ios::fill

get (1)
char_type fill() const;
set (2)
char_type fill (char_type fillch);
Get/set fill character
The first form (1) returns the fill character.

The second form (2) sets fillch as the new fill character and returns the fill character used before the call.

The fill character is the character used by output insertion functions to fill spaces when padding results to the field width.

The parametric manipulator setfill can also be used to set the fill character.

引數

fillch
the new fill character.
成員型別 char_type 是流使用的字元型別(即其第一個類模板引數 charT)。

返回值

The value of the fill character before the call.
成員型別 char_type 是流使用的字元型別(即其第一個類模板引數 charT)。

示例

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// using the fill character
#include <iostream>     // std::cout

int main () {
  char prev;

  std::cout.width (10);
  std::cout << 40 << '\n';

  prev = std::cout.fill ('x');
  std::cout.width (10);
  std::cout << 40 << '\n';

  std::cout.fill(prev);

  return 0;
}

輸出
        40
xxxxxxxx40


資料競爭

Accesses (1) or modifies (2) the stream object.
併發訪問同一個流物件可能導致資料爭用。

異常安全

基本保證:如果丟擲異常,流處於有效狀態。

另見