C ++，如何标记这个字符串？

Question

How can I get string like "Ac milan" and "Real Madryt" if they are separated with whitespace?

Here is my attempt:

string linia = "Ac milan ; Real Madryt ; 0 ; 2";
str = new char [linia.size()+1];
strcpy(str, linia.c_str());
sscanf(str, "%s ; %s ; %d ; %d", a, b, &c, &d);

but it doesn't work; I have: a= Ac; b = (null); c=0; d=2;

Answer 1

Yes, sscanf can do what you're asking for, using a scanset conversion:

#include <stdio.h>
#include <iostream>
#include <string>

int main(){ 

    char a[20], b[20];
    int c=0, d=0;
    std::string linia("Ac milan ; Real Madryt ; 0 ; 2");
    sscanf(linia.c_str(), " %19[^;]; %19[^;] ;%d ;%d", a, b, &c, &d);

    std::cout << a << "\n" << b << "\n" << c << "\n" << d << "\n";
    return 0;
}

The output produced by this is:

Ac milan
Real Madryt
0
2

Answer 2

If you want to go the C++ way, you can use getline , using ; as the delimiter, as follows.

string s = "Ac milan ; Real Madryt ; 0 ; 2";
string s0, s1;
istringstream iss(s);
getline(iss, s0, ';');
getline(iss, s1, ';');

Answer 3

Looks like you have ; as a separator character in the string so you can split the string based on that character. boost::split is useful for this:

string linia = "Ac milan ; Real Madryt ; 0 ; 2";
list<string> splitresults;

boost::split(splitresults, linia, boost::is_any_of(";"));

See Split a string in C++? for other techniques for splitting strings.

Answer 4

you can also use the std::string::find_first_of() method that allows you to search for character (delimiters) starting from a given position, eg

size_t tok_end = linia.find_first_of(";", prev_tok_end+1);
token = linia.substr(prev_tok_end+1, prev_tok_end+1 - tok_end);

However, the boost solution is the most elegant.