strcmpstrncmp

strcmp的原型翻译string compare，作用：字符串比较，而且仅限于字符串大小的比较；原型：int strcmp(const char *s1, const char *s2); 返回值： s1 = s2 ret = 0 s1 > s2 ret = 1 s1 < s2 ret = -1

实例：

#include <stdio.h> int main(void) { char arr1[10] = "ABCDEF"; char arr2[10] = "ABCDEF"; char arr3[10] = "6666"; char arr4[10] = "5555"; char arr5[10] = "111"; char arr6[10] = "222"; printf("vl1 = %d.\n", strcmp(arr1, arr2)); printf("vl2 = %d.\n", strcmp(arr3, arr4)); printf("vl3 = %d.\n", strcmp(arr5, arr6)); return 0; }

输出结果： // vl1 = 0. // vl2 = 1. // vl3 = -1.

strncmp是用来比较两个字符串前n个字节大小，区分大小写。原型：int strncmp(const char *s1, const char *s2, size_t n); 返回值和strcmp一样； 返回值：                s1 = s2          ret = 0                s1 > s2          ret = 1                s1 < s2          ret = -1