C++ string long double转char*

long

long q = 10;
char s[8];
char* output;
sprintf(s, "%ld", q);
output = s;

 

double

double d = 10;
char s1[8];
sprintf(s1, "%.2lf", d);

 

string

str.data();

 

 

%.后的数字为保留几位小数点