C语言生成随机字符串（代码实例）

// C语言生成随机字符.  
// VS2017 15.6.4  
  
#include <stdio.h>  
#include <stdlib.h>  
#include <time.h>  
  
const unsigned char allChar[63] = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";  
void generateString(unsigned char * dest, unsigned int len);  
  
int main()  
{  
    const unsigned int strlen = 20;  
    unsigned char str[strlen + 1] = {};  
  
    generateString(str, strlen);  
  
    printf("%s\n", str);  
      
    return 0;  
}  
  
void generateString(unsigned char * dest, const unsigned int len)  
{  
    unsigned int cnt, randNo;  
    srand((unsigned int)time(NULL));  
  
    for (cnt = 0; cnt<len; cnt++)  
    {  
        randNo = rand() % 62;  
        *dest = allChar[randNo];  
        dest++;  
    }  
  
    *dest = '\0';  
}