可能重复:
如何分割字符串?
将字符串拆分为字符串向量的正确方法是什么。分隔符是空格或逗号。
可能重复:
如何分割字符串?
将字符串拆分为字符串向量的正确方法是什么。分隔符是空格或逗号。
Answers:
对于以空格分隔的字符串,则可以执行以下操作:
std::string s = "What is the right way to split a string into a vector of strings";
std::stringstream ss(s);
std::istream_iterator<std::string> begin(ss);
std::istream_iterator<std::string> end;
std::vector<std::string> vstrings(begin, end);
std::copy(vstrings.begin(), vstrings.end(), std::ostream_iterator<std::string>(std::cout, "\n"));
输出:
What
is
the
right
way
to
split
a
string
into
a
vector
of
strings
struct tokens: std::ctype<char>
{
tokens(): std::ctype<char>(get_table()) {}
static std::ctype_base::mask const* get_table()
{
typedef std::ctype<char> cctype;
static const cctype::mask *const_rc= cctype::classic_table();
static cctype::mask rc[cctype::table_size];
std::memcpy(rc, const_rc, cctype::table_size * sizeof(cctype::mask));
rc[','] = std::ctype_base::space;
rc[' '] = std::ctype_base::space;
return &rc[0];
}
};
std::string s = "right way, wrong way, correct way";
std::stringstream ss(s);
ss.imbue(std::locale(std::locale(), new tokens()));
std::istream_iterator<std::string> begin(ss);
std::istream_iterator<std::string> end;
std::vector<std::string> vstrings(begin, end);
std::copy(vstrings.begin(), vstrings.end(), std::ostream_iterator<std::string>(std::cout, "\n"));
输出:
right
way
wrong
way
correct
way
std::vector<std::string> vstrings(begin, end);IMO会更好,但是我想我们不知道发问者是否正在构建矢量,还是希望填充先前存在的矢量。
ss.imbue(std::locale(std::locale(), new tokens()))某处创建的令牌结构?
auto loc = std::make_shared<tokens>(),然后通过ss.imbue(..., loc.get()));。那应该工作。
一种方便的方法是boost的字符串算法库。
#include <boost/algorithm/string/classification.hpp> // Include boost::for is_any_of
#include <boost/algorithm/string/split.hpp> // Include for boost::split
// ...
std::vector<std::string> words;
std::string s;
boost::split(words, s, boost::is_any_of(", "), boost::token_compress_on);
vector<string> split(string str, string token){
vector<string>result;
while(str.size()){
int index = str.find(token);
if(index!=string::npos){
result.push_back(str.substr(0,index));
str = str.substr(index+token.size());
if(str.size()==0)result.push_back(str);
}else{
result.push_back(str);
str = "";
}
}
return result;
}
split(“ 1,2,3”,“,”)==> [“ 1”,“ 2”,“ 3”]
split(“ 1,2,”,“,”)==> [“ 1”,“ 2”,“”]
split(“ 1token2token3”,“ token”)==> [“ 1”,“ 2”,“ 3”]
Techie Delight的调整版本:
#include <string>
#include <vector>
std::vector<std::string> split(const std::string& str, char delim) {
std::vector<std::string> strings;
size_t start;
size_t end = 0;
while ((start = str.find_first_not_of(delim, end)) != std::string::npos) {
end = str.find(delim, start);
strings.push_back(str.substr(start, end - start));
}
return strings;
}
我做了这个自定义函数,它将线转换为矢量
#include <iostream>
#include <vector>
#include <ctime>
#include <string>
using namespace std;
int main(){
string line;
getline(cin, line);
int len = line.length();
vector<string> subArray;
for (int j = 0, k = 0; j < len; j++) {
if (line[j] == ' ') {
string ch = line.substr(k, j - k);
k = j+1;
subArray.push_back(ch);
}
if (j == len - 1) {
string ch = line.substr(k, j - k+1);
subArray.push_back(ch);
}
}
return 0;
}
std::vector<std::string> split(std::string text, char delim) {
std::string line;
std::vector<std::string> vec;
std::stringstream ss(text);
while(std::getline(ss, line, delim)) {
vec.push_back(line);
}
return vec;
}
split("String will be split", ' ') -> {"String", "will", "be", "split"}
split("Hello, how are you?", ',') -> {"Hello", "how are you?"}
我编写此自定义函数将为您提供帮助。但是讨论一下时间复杂度。
std::vector<std::string> words;
std::string s;
std::string separator = ",";
while(s.find(separator) != std::string::npos){
separatorIndex = s.find(separator)
vtags.push_back(s.substr(0, separatorIndex ));
words= s.substr(separatorIndex + 1, s.length());
}
words.push_back(s);