这个split 不错 我喜欢的

// stdLibStringSplit.cpp : 定义控制台应用程序的入口点。
//


#include "stdafx.h"
/********************************************


the tokenize function for std::string


*********************************************/
#include <string>
#include <vector>
#include <iostream>
using namespace std;


typedef basic_string<char>::size_type S_T;
static const S_T npos = -1;


////trim指示是否保留空串，默认为保留。
vector<string> tokenize(const string& src, string tok, bool trim=false, string null_subst="")
{
if( src.empty() || tok.empty() ) throw "tokenize: empty string\0";
vector<string> v;
S_T pre_index = 0, index = 0, len = 0;
while( (index = src.find_first_of(tok, pre_index)) != npos )
{
if( (len = index-pre_index)!=0 )
v.push_back(src.substr(pre_index, len));
else if(trim==false)
v.push_back(null_subst);
pre_index = index+1;
}
string endstr = src.substr(pre_index);
if( trim==false )
v.push_back( endstr.empty()? null_subst:endstr );
else if( !endstr.empty() )
v.push_back(endstr);return v;
}




////使用一个完整的串delimit（而不是其中的某个字符）来分割src串,没有trim选项，即严格分割。


vector<string> split(const string& src, string delimit,string null_subst="")
{
if( src.empty() || delimit.empty() ) 
throw "split: empty string\0";


vector<string> v;
S_T deli_len = delimit.size();
long index = npos, last_search_position = 0;
while( (index=src.find(delimit, last_search_position))!=npos )
{
if(index==last_search_position)
v.push_back(null_subst);
else
v.push_back( src.substr(last_search_position, index-last_search_position) );
last_search_position = index + deli_len;
}
string last_one = src.substr(last_search_position);
v.push_back( last_one.empty()? null_subst:last_one );
return v;
}


// test
int main(void)
{
string src = ",ab\r\ncde\r\nfg,,\r\n " ;
string tok = "\r\n";


vector<string> v1 = tokenize(src, tok ,true);
vector<string> v2 = tokenize(src, tok ,false, "<null>");


cout<<"-------------v1:"<<endl;
for(int i=0; i<v1.size();i++)
{
cout<<v1[i].c_str()<<endl;
}


cout<<"-------------v2:"<<endl;
for(int j=0; j<v2.size();j++)
{
cout<<v2[j].c_str()<<endl;
}


try
{
string s = "######123#4###56########789###";
string del = "";//"###";
vector<string> v3 = split(s, del, "<null>");
cout<<"-------------v3:"<<endl;
for(int k=0; k<v3.size();k++)
{
cout<<v3[k].c_str()<<endl;
}
}
catch (char *s)
{
cout<<s<<endl;
}
return 0;
}