如何将空字符串存储到向量中 我是C++新手,我不知道用定界符分割一个字符串,把子串放进向量。< /P>

如何将空字符串存储到向量中 我是C++新手,我不知道用定界符分割一个字符串,把子串放进向量。< /P>,c++,string,vector,C++,String,Vector,我的代码如下: vector<string> split(const string &s, const string &delim) { string::size_type pos = s.find_first_of(delim,0); int start = 0; vector<string> tokens; while(start < s.size()) { if(start

我的代码如下:

vector<string> split(const string &s, const string &delim)
{   
    string::size_type pos = s.find_first_of(delim,0);
    int start = 0;
    vector<string> tokens;

    while(start < s.size())
    {
            if(start++ != pos + 1)
                    tokens.push_back(" ");
            pos = s.find_first_of(delim, start);
            tokens.push_back(s.substr(start, pos - start));
    }

    for(vector<string>::size_type i = 0; i != tokens.size(); ++i)
            cout << tokens[i];

    return tokens;
}
减去引号

但我的代码目前的输出是

ab b    cd d  

任何帮助都将不胜感激。

您的循环似乎没有做正确的事情:您一个字符一个字符地行走,在每次迭代中一个字符地前进
开始
。我怀疑您实际上想要一个当前位置,查找下一个分隔符,将当前位置和分隔符之间的字符串添加到结果中,并将当前位置设置为分隔符后面的字符:

for (std::string::size_type start(0); start != s.npos; )
{
    std::string::size_type end(s.find_first_of(delim, start));
    tokens.push_back(s.substr(start, end != s.npos? end - start: end));
    start = end != s.npos? end + 1: s.npos;
}

你的循环似乎做得不对:你一个字符一个字符地走,在每次迭代中一个一个地前进
start
。我怀疑您实际上想要一个当前位置,查找下一个分隔符,将当前位置和分隔符之间的字符串添加到结果中,并将当前位置设置为分隔符后面的字符:

for (std::string::size_type start(0); start != s.npos; )
{
    std::string::size_type end(s.find_first_of(delim, start));
    tokens.push_back(s.substr(start, end != s.npos? end - start: end));
    start = end != s.npos? end + 1: s.npos;
}
这就是诀窍

#include <iostream>
#include <vector>

using namespace std;

vector<string> split(string record, string token) {
    vector<string> results;
    size_t startPos = 0;
    size_t pos = 0;

    // Step: If either argument is empty then return
    // an empty vector.
    if (record.length() == 0 || token.length() == 0) {
        return results;
    }

    // Step: Go through the record and split up the data.
    while(startPos < record.length()) {
        pos = record.find(token, startPos);
        if (pos == string::npos) {
            break;
        }

        results.push_back(record.substr(startPos, pos - startPos));
        startPos = pos + token.length();
    }

    // Step: Get the last (or only bit).
    results.push_back(record.substr(startPos, record.length() - startPos));

    // Step: Return the results of the split.
    return results;
}

void printData(vector<string> list) {
    for(vector<string>::iterator it = list.begin(); it < list.end(); it++) {
        cout << *it << endl;
    }
}

int main(int argc, char** argv) {
    string record = "";
    string delim = "";

    if (argc == 3) {
        record = argv[1];
        delim = argv[2];
        printData(split(record,delim));
    } else {
        string record = "comma,delimited,data";
        string delim = ",";
        printData(split(record,delim));

        record = "One<--->Two<--->Three<--->Four";
        delim = "<--->";
        printData(split(record,delim));
    }
}
#包括
#包括
使用名称空间std;
向量拆分(字符串记录、字符串标记){
矢量结果;
大小\u t startPos=0;
大小\u t pos=0;
//步骤:如果任一参数为空,则返回
//空向量。
if(record.length()==0 | | token.length()==0){
返回结果;
}
//步骤:检查记录并拆分数据。
while(startPos
#include <iostream>
#include <vector>

using namespace std;

vector<string> split(string record, string token) {
    vector<string> results;
    size_t startPos = 0;
    size_t pos = 0;

    // Step: If either argument is empty then return
    // an empty vector.
    if (record.length() == 0 || token.length() == 0) {
        return results;
    }

    // Step: Go through the record and split up the data.
    while(startPos < record.length()) {
        pos = record.find(token, startPos);
        if (pos == string::npos) {
            break;
        }

        results.push_back(record.substr(startPos, pos - startPos));
        startPos = pos + token.length();
    }

    // Step: Get the last (or only bit).
    results.push_back(record.substr(startPos, record.length() - startPos));

    // Step: Return the results of the split.
    return results;
}

void printData(vector<string> list) {
    for(vector<string>::iterator it = list.begin(); it < list.end(); it++) {
        cout << *it << endl;
    }
}

int main(int argc, char** argv) {
    string record = "";
    string delim = "";

    if (argc == 3) {
        record = argv[1];
        delim = argv[2];
        printData(split(record,delim));
    } else {
        string record = "comma,delimited,data";
        string delim = ",";
        printData(split(record,delim));

        record = "One<--->Two<--->Three<--->Four";
        delim = "<--->";
        printData(split(record,delim));
    }
}
#包括
#包括
使用名称空间std;
向量拆分(字符串记录、字符串标记){
矢量结果;
大小\u t startPos=0;
大小\u t pos=0;
//步骤:如果任一参数为空,则返回
//空向量。
if(record.length()==0 | | token.length()==0){
返回结果;
}
//步骤:检查记录并拆分数据。
while(startPos这里有一些相关的问题可能会有所帮助:这里有一些相关的问题可能会有所帮助: