C++如何判断变量类型

使用 typeid 判断其类型:(需要在编译语言选项中选择 RTTI 编译选项)，例子:【引用自这里】，详情可以看这里

#include <iostream >
#include <typeinfo.h>
using namespace std;
int main()
{
	char *p=NULL;
	char str[]="hello world";
	cout<<typeid(p).name()<<endl;
	cout<<typeid(str).name()<<endl;
	return 0;
}

打印出的类型并不是可以直接读懂的，可以参考下面的类型对照表【参考自这里】解读。

  <builtin-type> ::= v	# void
		 						::= w	# wchar_t
		 						::= b	# bool
		 						::= c	# char
		 						::= a	# signed char
		 						::= h	# unsigned char
		 						::= s	# short
		 						::= t	# unsigned short
		 						::= i	# int
		 						::= j	# unsigned int
		 						::= l	# long
		 						::= m	# unsigned long
		 						::= x	# long long, __int64
		 						::= y	# unsigned long long, __int64
		 						::= n	# __int128
		 						::= o	# unsigned __int128
		 						::= f	# float
		 						::= d	# double
		 						::= e	# long double, __float80
		 						::= g	# __float128
		 						::= z	# ellipsis
                 				::= Dd # IEEE 754r decimal floating point (64 bits)
                 				::= De # IEEE 754r decimal floating point (128 bits)
                 				::= Df # IEEE 754r decimal floating point (32 bits)
                 				::= Dh # IEEE 754r half-precision floating point (16 bits)
                 				::= DF <number> _ # ISO/IEC TS 18661 binary floating point type _FloatN (N bits)
                 				::= DB <number> _        # C23 signed _BitInt(N)
                 				::= DB <instantiation-dependent expression> _ # C23 signed _BitInt(N)
                 				::= DU <number> _        # C23 unsigned _BitInt(N)
                 				::= DU <instantiation-dependent expression> _ # C23 unsigned _BitInt(N)
                 				::= Di # char32_t
                 				::= Ds # char16_t
                 				::= Du # char8_t
                 				::= Da # auto
                 				::= Dc # decltype(auto)
                 				::= Dn # std::nullptr_t (i.e., decltype(nullptr))
		 						::= u <source-name> [<template-args>] # vendor extended type