C_提升__字符串初始化

2020-04-24

#include<stdio.h>
#include<string.h>
/*C语言没有字符串类型，通过字符数组模拟
    C语言字符串，以字符 ‘\0’ ,数字0    
*/
int main()
{    
    //不指定长度，没有0结束符
    char buf[] = {'a','b','c'};
   printf("buf = %s\n",buf);           //乱码
      
   //指定长度，后面没有赋值的元素，自动补0
   char buf1[100] = {'a','b','c'};
   printf("buf1 = %s\n",buf1);
  
   //所有元素赋值为0
   char buf2[100] = {0};

   char buf4[2] = {'1','2','3','4'};//数组越界
  
   char buf5[50] = {'a','1','0','7'};

   char buf6[50] = {'a','1',0,'7'};

   char buf7[50] = {'a','1','\0','7'};  //数组中‘\0’与数字0等价  为结束符
   //使用字符串初始化，常用
   char buf8[] = "sadfsdfasd";
//strlen: 测字符串长度，不包含数字0，字符‘\0’
//sizeof:测数组长度，包含数字0，字符‘\0’
   printf("strlen = %d,sizeof(buf8) = %d\n",strlen(buf8),sizeof(buf8));
 
   char buf9[50] = "adsfsdf";
   printf("sizeof(buf9) = %d\n",sizeof(buf9))  //sizeof(buf9) = 100




    return 0;
}