How can I read in two characters from a file into a std::string?
the long way:
fstream f("myfile.bin ", ios::binary | ios:in); // Opened for read
binary...
unsigned char buffer[3];
buffer[2] = '\0';
f.read(buffer, 2);
std::string x(buffer);
Got a better way?
6  2351 
SpreadTooThin wrote:
How can I read in two characters from a file into a std::string?
the long way:
fstream f("myfile.bin ", ios::binary | ios:in); // Opened for read binary...
unsigned char buffer[3];
buffer[2] = '\0';
f.read(buffer, 2);
std::string x(buffer);
Got a better way?
fstream f("myfile.bin ", ios::binary | ios:in);
char buffer[2];
f.read(buffer, 2);
std::string x(buffer, buffer+2);
They do behave differently.
On Jun 6, 10:11 pm, SpreadTooThin <bjobrie...@gma il.comwrote:
How can I read in two characters from a file into a std::string?
the long way:
fstream f("myfile.bin ", ios::binary | ios:in); // Opened for read
binary...
unsigned char buffer[3];
buffer[2] = '\0';
f.read(buffer, 2);
std::string x(buffer);
Got a better way?
std::string x ;
x += f.get() ;
x += f.get() ;
(Of course, you'll want to check that you actually did get two
characters.)
Something that will work with all current implementations , and
will be guaranteed by the next version of the standard:
std::string x( 2, ' ' ) ;
f.read( &x[ 0 ], 2 ) ;
--
James Kanze (GABI Software) email:ja******* **@gmail.com
Conseils en informatique orientée objet/
Beratung in objektorientier ter Datenverarbeitu ng
9 place Sémard, 78210 St.-Cyr-l'École, France, +33 (0)1 30 23 00 34
James Kanze wrote:
....
Something that will work with all current implementations , and
will be guaranteed by the next version of the standard:
Do you have a reference to the this proposal (contiguous strings)?
On 2007-06-07 01:59:03 -0700, Gianni Mariani <gi*******@mari ani.wssaid:
James Kanze wrote:
...
>Something that will work with all current implementations , and
will be guaranteed by the next version of the standard:
Do you have a reference to the this proposal (contiguous strings)?
See: http://www.open-std.org/jtc1/sc22/wg...fects.html#530
--
Clark S. Cox III cl*******@gmail .com
On Jun 7, 10:59 am, Gianni Mariani <gi3nos...@mari ani.wswrote:
James Kanze wrote:
...
Something that will work with all current implementations , and
will be guaranteed by the next version of the standard:
Do you have a reference to the this proposal (contiguous strings)?
It's in the current draft (N2134): "The char-like objects in a
basic_string object shall be stored contiguously. That is, for
any basic_string object s, the identity &*(s.begin() + n) ==
&*s.begin() + n shall hold for all values of n such that 0 <= n
< s.size()." From what I understand, a non-const version of
data() will also be added (as well as const and non-const data()
functions to std::vector), in order to obtain the address in a
way somewhat more transparently than &s[0].
--
James Kanze (GABI Software) email:ja******* **@gmail.com
Conseils en informatique orientée objet/
Beratung in objektorientier ter Datenverarbeitu ng
9 place Sémard, 78210 St.-Cyr-l'École, France, +33 (0)1 30 23 00 34
James Kanze wrote:
>
It's in the current draft (N2134)
Just so everyone's up to date, the current draft (reflecting changes
made at the April, 2007 meeting) is N2284.
--
-- Pete
Roundhouse Consulting, Ltd. ( www.versatilecoding.com)
Author of "The Standard C++ Library Extensions: a Tutorial and
Reference." ( www.petebecker.com/tr1book) This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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