string轉const char*

string s = “abc”;
const char* c_s = s.c_str();

const char*轉string
直接賦值即可

const char* c_s = “abc”;
string s(c_s);

string轉char*

string s = “abc”;
char* c;
const int len = s.length();
c = new char[len+1];
strcpy(c,s.c_str());

char*轉string

char* c = “abc”;
string s©;

const char轉char

const char* cpc = “abc”;
char* pc = new char[100];//足夠長
strcpy(pc,cpc);

char轉const char
直接賦值即可

char* pc = “abc”;
const char* cpc = pc;