01、C語言字符串和數據的統一

本片文章主要介紹怎麼把C語言的字符串當成數字使用>>>>以下給出源碼解析

#include "stdio.h"
static void get_sizeof(void)
{
	printf("|<<<----------------------------------------------->>>|\r\n");
	printf("|<<<           sizeof(char)=%dBytes                 >>>|\r\n",sizeof(char));
	printf("|<<<           sizeof(short)=%dBytes                >>>|\r\n",sizeof(short));
	printf("|<<<           sizeof(int)=%dBytes                  >>>|\r\n",sizeof(int));
	printf("|<<<           sizeof(long)=%dBytes                 >>>|\r\n",sizeof(long));
	printf("|<<<           sizeof(float)=%dBytes                >>>|\r\n",sizeof(float));
	printf("|<<<           sizeof(double)=%dBytes               >>>|\r\n",sizeof(double));
    printf("|<<<----------------------------------------------->>>|\r\n");	
}
int main()
{
	//C語言之如何把字符串當成數字
	get_sizeof();
	{
	   //檢測char*型變量的佔用空間
	   printf("%d\r\n",sizeof(char*));
	   //檢測unsigned int型變量空間
	   printf("%d\r\n",sizeof(unsigned int));
	   //如果sizeof(char*)=sizeof(unsigned int),或者sizeof(unsigned int)>sizeof(char*)
	   //推出:強制轉換->安全->不會溢出
	   {
		  unsigned int str_num;
		  //字符串->賦值給數字型變量
		  str_num=(unsigned int)("一二三");
		  printf("%s\r\n",(char*)(str_num));
		  //數字->賦值給數字型變量
		  str_num=1234;
		  printf("%d\r\n",str_num);
	   }
	   //while(1);
	   return 0;
	}
	//強制轉時要保證:   sizeof(被轉換變量的類型)<=sizeof(強制轉換類型)
	//-------字符串和數字統一思想------//
	//write by QQ羣:649692007、更多交流---------------//
}