C++ 11 开始支持正则表达式了，我用的编译器是 TDM-GCC 4.9.2 64-bit，要在菜单命令：“工具-->编译选项->编译器”中设置配置，编译时加入以下命令文本框里添加 “-std=c++11”，如下图所示：

刚接触正则表达式，初步学了点皮毛记录一下。直接上代码：

#include <iostream>
#include <string>
#include <vector>
#include <regex>
using namespace std;

int regexSplit(string&,const string,vector<string>&,int);
 
int main(void)
{
 	vector <string> vect;
	string str = "(12.3e+10-0.018e-5)+(11.006-7.)+.89";
	string reg[11]={
		"(\\d+)",				/*整数，包括0开头的 */ 
		"([1-9]\\d*)",			/*错：整数，但取不到0 */ 
		"(0|[1-9]\\d*)",		/*全部整数 */ 
		"(\\d+\\.\\d+)",		/*小数不包括整数 */ 
		"(\\d*\\.?\\d+)",		/*错：整数或小数，但包括7. */ 
		"(\\d+\\.?\\d*)",		/*错：整数或小数，但包括.89 */ 
		"(\\d+|\\d+\\.\\d+)",	/*整数或小数 */ 
		"-?(\\d+|\\d+\\.\\d+)",	/*正数或负数 */ 
		"\\([^()]*\\)",			/*匹配成对的括号 */ 
		"-?(\\d+\\.\\d+)e[+-]\\d+",	/*科学记数法 */	
		"-?((\\d+|\\d+\\.\\d+)|(\\d+\\.\\d+)e[+-]\\d+)"	/*实数 */
		};
	cout<<str<<endl<<"--------------"<<endl;
	for (auto a:reg){
		regexSplit(str,a,vect,0);
		cout<<"pattern:"<<a<<endl<<"string: ";
		for(auto v:vect) cout<<v<<" ";
		vect.clear();
		cout<<endl<<"=============="<<endl;
	}
	return 0;
 }
 
int regexSplit(string &str,const string str_reg,vector<string>&vect,int pos)
{
	int i=0;
	if (pos!=-1) pos=0;  //pos=0 匹配到的位置，pos=-1匹配位置的前一字串 
	regex Pattern(str_reg); 
    sregex_token_iterator it(str.begin(),str.end(),Pattern, pos); 
    sregex_token_iterator end;
    for(;it!=end;++it,i++) vect.push_back(*it); 
    return i;  //if (i==0) 没有匹配到，else 匹配到的个数 i
 } 

输出结果：

(12.3e+10-0.018e-5)+(11.006-7.)+.89
--------------
pattern:(\d+)
string: 12 3 10 0 018 5 11 006 7 89
==============
pattern:([1-9]\d*)
string: 12 3 10 18 5 11 6 7 89
==============
pattern:(0|[1-9]\d*)
string: 12 3 10 0 0 18 5 11 0 0 6 7 89
==============
pattern:(\d+\.\d+)
string: 12.3 0.018 11.006
==============
pattern:(\d*\.?\d+)
string: 12.3 10 0.018 5 11.006 7 .89
==============
pattern:(\d+\.?\d*)
string: 12.3 10 0.018 5 11.006 7. 89
==============
pattern:(\d+|\d+\.\d+)
string: 12.3 10 0.018 5 11.006 7 89
==============
pattern:-?(\d+|\d+\.\d+)
string: 12.3 10 -0.018 -5 11.006 -7 89
==============
pattern:\([^()]*\)
string: (12.3e+10-0.018e-5) (11.006-7.)
==============
pattern:-?(\d+\.\d+)e[+-]\d+
string: 12.3e+10 -0.018e-5
==============
pattern:-?((\d+|\d+\.\d+)|(\d+\.\d+)e[+-]\d+)
string: 12.3e+10 -0.018e-5 11.006 -7 89
==============

--------------------------------
Process exited after 0.5831 seconds with return value 0
请按任意键继续. . .

附录：

特殊字符：

characters	description	matches
.	not newline	any character exceptline terminators(LF, CR, LS, PS).
\t	tab (HT)	a horizontal tab character (same as\u0009).
\n	newline (LF)	a newline (line feed) character (same as\u000A).
\v	vertical tab (VT)	a vertical tab character (same as\u000B).
\f	form feed (FF)	a form feed character (same as\u000C).
\r	carriage return (CR)	a carriage return character (same as\u000D).
\cletter	control code	a control code character whosecode unit valueis the same as the remainder of dividing thecode unit valueofletterby 32. For example:\cais the same as\u0001,\cbthe same as\u0002, and so on...
\xhh	ASCII character	a character whosecode unit valuehas an hex value equivalent to the two hex digitshh. For example:\x4cis the same asL, or\x23the same as#.
\uhhhh	unicode character	a character whosecode unit valuehas an hex value equivalent to the four hex digitshhhh.
\0	null	a null character (same as\u0000).
\int	backreference	the result of the submatch whose opening parenthesis is theint-th (intshall begin by a digit other than0). Seegroupsbelow for more info.
\d	digit	a decimal digit character
\D	not digit	any character that is not a decimal digit character
\s	whitespace	a whitespace character
\S	not whitespace	any character that is not a whitespace character
\w	word	an alphanumeric or underscore character
\W	not word	any character that is not an alphanumeric or underscore character
\character	character	the charactercharacteras it is, without interpreting its special meaning within a regex expression. Anycharactercan be escaped except those which form any of the special character sequences above. Needed for:^ $ \ . * + ? ( ) [ ] { } |
[class]	character class	the target character is part of the class
[^class]	negated character class	the target character is not part of the class

数量：

characters	times	effects
*	0 or more	The preceding atom is matched 0 or more times.
+	1 or more	The preceding atom is matched 1 or more times.
?	0 or 1	The preceding atom is optional (matched either 0 times or once).
{int}	int	The preceding atom is matched exactlyinttimes.
{int,}	intor more	The preceding atom is matchedintor more times.
{min,max}	betweenminandmax	The preceding atom is matched at leastmintimes, but not more thanmax.

分组：

characters	description	effects
(subpattern)	Group	Creates a backreference.
(?:subpattern)	Passive group	Does not create a backreference.

其他：

characters	description	condition for match
^	Beginning of line	Either it is the beginning of the target sequence, or follows aline terminator.
$	End of line	Either it is the end of the target sequence, or precedes aline terminator.
|	Separator	Separates two alternative patterns or subpatterns..