char*，const char*，string的相互轉換 C++

轉：https://www.cnblogs.com/wxmdevelop/p/4567857.html

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

2. const char轉string
   直接賦值即可
   constchar c_s =“abc”;
   string s(c_s);

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

4. char轉string
   char c =“abc”;
   string s©;

5. const char轉char
   constchar* cpc =“abc”;
   char* pc =newchar[100];//足夠長
   strcpy(pc,cpc);