C++ char*，const char*，string的相互转换

1. string转const char*

string s ="abc";
constchar* c_s = s.c_str();

2. const char*转string
直接赋值即可

constchar* c_s ="abc";
string s(c_s);

3. string转char*
string s ="abc";
char* c;
constint len = s.length();
c =newchar[len+1];
strcpy(c,s.c_str());

4. char*转string

char* c ="abc";
string s(c);

5. const char*转char*

constchar* cpc ="abc";
char* pc =newchar[100];//足够长
strcpy(pc,c