我是编程新手。我一直在尝试编写一个C++函数，根据给定的参数将字符串的内容拆分成一个字符串数组，例如：
string str = "___this_ is__ th_e str__ing we__ will use__";
应该返回字符串数组：
cout << stringArray[0]; // 'this'
cout << stringArray[1]; // ' is'
cout << stringArray[2]; // ' th'
cout << stringArray[3]; // 'e str'
cout << stringArray[4]; // 'ing we'
cout << stringArray[5]; // ' will use'
我使用向量和字符串来进行首次尝试：
vector<string> explode(const string& str, const char& ch) {
string next;
vector<string> result;
// For each character in the string
for (string::const_iterator it = str.begin(); it != str.end(); it++) {
// If we've hit the terminal character
if (*it == ch) {
// If we have some characters accumulated
if (!next.empty()) {
// Add them to the result vector
result.push_back(next);
next.clear();
}
} else {
// Accumulate the next character into the sequence
next += *it;
}
}
if (!next.empty())
result.push_back(next);
return result;
}
int main (int, char const **) {
std::string blah = "___this_ is__ th_e str__ing we__ will use__";
std::vector<std::string> result = explode(blah, '_');
for (size_t i = 0; i < result.size(); i++) {
cout << "\"" << result[i] << "\"" << endl;
}
return 0;
}
next 是否为空，如果不为空，则在循环之后将其附加到结果中。否则，分隔符后的最后一个元素将不会被包含在内。 - ddinchev#include <vector>
#include <string>
#include <sstream>
int main()
{
std::vector<std::string> result;
std::string str = "___this_ is__ th_e str__ing we__ will use__";
std::stringstream data(str);
std::string line;
while(std::getline(data,line,'_'))
{
result.push_back(line); // Note: You may get a couple of blank lines
// When multiple underscores are beside each other.
}
}
// 或者定义一个令牌
#include <vector>
#include <string>
#include <iterator>
#include <algorithm>
#include <sstream>
struct Token: public std::string // Yes I know this is nasty.
{ // But it is just to demosntrate the principle.
};
std::istream& operator>>(std::istream& s,Token& t)
{
std::getline(s,t,'_');
// ***
// Remove extra '_' characters from the stream.
char c;
while(s && ((c = s.get()) != '_')) {/*Do Nothing*/}
if (s)
{
s.unget(); // Put back the last char as it is not '_'
}
return s;
}
int main()
{
std::string str = "___this_ is__ th_e str__ing we__ will use__";
std::stringstream data(str);
std::vector<std::string> result(std::istream_iterator<Token>(data),
std::istream_iterator<Token>());
}
它对我有效：
#include <iostream>
#include <vector>
#include <string>
using namespace std;
vector<string> explode( const string &delimiter, const string &explodeme);
int main(int argc, char *argv[])
{
string str = "I have a lovely bunch of cocoa nuts";
cout<<str<<endl;
vector<string> v = explode(" ", str);
for(int i=0; i<v.size(); i++)
cout <<i << " ["<< v[i] <<"] " <<endl;
}
vector<string> explode( const string &delimiter, const string &str)
{
vector<string> arr;
int strleng = str.length();
int delleng = delimiter.length();
if (delleng==0)
return arr;//no change
int i=0;
int k=0;
while( i<strleng )
{
int j=0;
while (i+j<strleng && j<delleng && str[i+j]==delimiter[j])
j++;
if (j==delleng)//found delimiter
{
arr.push_back( str.substr(k, i-k) );
i+=delleng;
k=i;
}
else
{
i++;
}
}
arr.push_back( str.substr(k, i-k) );
return arr;
}
来源 : http://www.zedwood.com/article/106/cpp-explode-function
这是一篇关于C++中explode函数的文章。explode函数可以将字符串按照指定分隔符进行拆分，并返回一个包含拆分后子串的数组。本文介绍了explode函数的实现方法和使用示例，希望对C++开发者有所帮助。如果你坚持将 stringArray 定义为数组而不是 std::vector<>（后者才是正确的做法），那么你必须要么：
使用 vector 更容易，vector::push_back() 可以将新内容附加到末尾。所以：
vector* explode(string s){
vector<string> *v = new vector<string>
//...
// in a loop
v->push_back(string_fragment);
//...
return v;
}
实际上不需要为了完整性而保留。
要返回字符串数组，您可以使用char **。
例如：
char ** explode(const char *in){
...
}
顺便提一下-- 调用函数如何知道返回的数组有多少元素？你也必须解决这个问题。除非受到外部限制，否则使用std :: vector<>...
(std::vector<std::string>)，通过 push_back 将每个标记附加到其中，然后从 tokenize 函数中返回它。我认为我写了一个更简单的解决方案。
std::vector<std::string> explode(const std::string& string, const char delimiter) {
std::vector<std::string> result;
unsigned int start = 0, pos = 0;
while (pos != string.length()) {
if (string.at(pos) == delimiter || pos + 1 == string.length()) {
unsigned int size = (pos - start) + ((pos + 1) == string.length() ? 1 : 0);
if (size != 0) { // Make this 'if' as a option? like a parameter with removeEmptyString?
result.push_back(string.substr(start, size));
}
start = pos + 1;
}
pos++;
}
return std::move(result);
}
以下是代码：
template <typename OutputIterator>
int explode(const string &s, const char c, OutputIterator output) {
stringstream data(s);
string line;
int i=0;
while(std::getline(data,line,c)) { *output++ = line; i++; }
return i;
}
int main(...) {
string test="H:AMBV4:2:182.45:182.45:182.45:182.45:182.41:32:17700:3229365:201008121711:0";
cout << test << endl;
vector<string> event;
**This is the main call**
int evts = explode(test,':', back_inserter(event));
for (int k=0; k<evts; k++)
cout << event[k] << "~";
cout << endl;
}
输出
H:AMBV4:2:182.45:182.45:182.45:182.45:182.41:32:17700:3229365:201008121711:0
H~AMBV4~2~182.45~182.45~182.45~182.45~182.41~32~17700~3229365~201008121711~0~
这是我编写的代码（完整版）。也许对于有相同需求的人来说会有用。
#include <string>
#include <iostream>
#include <sstream>
#include <vector>
using namespace std;
int main(){
std::string s = "scott:tiger:mushroom";
std::string delimiter = ":";
std::vector<std::string> outputArr;
size_t pos = 0;
std::string token;
while ((pos = s.find(delimiter)) != std::string::npos) {
token = s.substr(0, pos);
s.erase(0, pos + delimiter.length());
outputArr.push_back(token);
}
outputArr.push_back(s);
// Printing Array to see the results
std::cout<<"====================================================================================\n";
for ( int i=0;i<outputArr.size();i++){
std::cout<<outputArr[i]<<"\n";
}
std::cout<<"====================================================================================\n";
}
干杯！！