std::basic_istream::getline
basic_istream& getline( char_type* s, std::streamsize count );
|
(1) | |
basic_istream& getline( char_type* s, std::streamsize count, char_type delim );
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(2) | |
Extracts characters from stream until end of line or the specified delimiter delim
.
The first version is equivalent to getline(s, count, widen('\n')).
Behaves as UnformattedInputFunction
. After constructing and checking the sentry object, extracts characters from *this
and stores them in successive locations of the array whose first element is pointed to by s
, until any of the following occurs (tested in the order shown):
- end of file condition occurs in the input sequence (in which case setstate(eofbit) is executed)
- the next available character
c
is the delimiter, as determined by Traits::eq(c, delim). The delimiter is extracted (unlike basic_istream::get()) and counted towardsgcount()
, but is not stored.
- count-1 characters have been extracted (in which case setstate(failbit) is executed).
If the function extracts no characters (e.g. if count < 1), setstate(failbit) is executed.
In any case, if count>0
, it then stores a null character CharT()
into the next successive location of the array and updates gcount()
.
Contents |
[edit] Notes
Because condition #2 is tested before condition #3, the input line that exactly fits the buffer does not trigger failbit.
Because the terminating character is counted as an extracted character, an empty input line does not trigger failbit.
[edit] Parameters
s | - | pointer to the character string to store the characters to |
count | - | size of character string pointed to by s
|
delim | - | delimiting character to stop the extraction at. It is extracted but not stored. |
[edit] Return value
*this
[edit] Exceptions
If an internal operation throws an exception, it is caught and badbit is set. If exceptions() is set for badbit
, the exception is rethrown.
[edit] Example
#include <iostream> #include <sstream> #include <vector> #include <array> int main() { std::istringstream input("abc|def|gh"); std::vector<std::array<char, 4>> v; // note: the following loop terminates when std::ios_base::operator bool() // on the stream returned from getline() returns false for (std::array<char, 4> a; input.getline(&a[0], 4, '|'); ) { v.push_back(a); } for (auto& a : v) { std::cout << &a[0] << '\n'; } }
Output:
abc def gh
[edit] See also
read data from an I/O stream into a string (function template) |
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extracts formatted data (public member function) |
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extracts characters (public member function) |
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extracts blocks of characters (public member function) |