Question

const char* s1   = "teststirg";  
const char  s2[] = "teststirg";

I want a method tell me that s1 is “char*” and s2 is “char[]”,how to write the method?

Answer 1

Use templates:

template<typename T, unsigned int SIZE>
bool IsArray (T (&a)[SIZE]) { return true; }

template<typename T>
bool IsArray (T *p) { return false; }

This will evaluate at runtime.
Usage:

if(IsArray(s1))
...

if(IsArray(s2))
...

If interested, you can use some advance techniques, which will tell you this as compile time.

Edit:

typedef char (&yes)[2];

template<typename T, unsigned int SIZE>
yes IsArray (T (&a)[SIZE]);

template<typename T>
char IsArray (T *p);

Usage:

if(sizeof(IsArray(s1)) == sizeof(yes))
...
if(sizeof(IsArray(s2)) == sizeof(yes))
...