一.字符串拷贝strcpy
#include#include void strcpy(char* s1,char* s2){ char* ps1=s1; char* ps2=s2; while(*ps2!=' '){ *ps1=*ps2; ps1++;ps2++; } *ps1=' '; } int main(){ char s1[100]="I LOVE YOU."; char s2[100]="And you?"; strcpy(s1,s2); printf("%s",s1); return 0; }
s2的And you 覆盖了s1中的I LOVE YOU.
二.字符串长度strlen
#include#include int strlen(char* s){ int count=0; while(*s !=' '){ count++; s++; } return count; } int main() { char* s="I LOVE YOU."; int count=strlen(s); printf("%d",count); return 0; }
输出结果为 11，即“I LOVE YOU."字符串长为11
三.字符串连接strcat
#include#include void stract(char* ps1,char* ps2){ while(*ps1 !=' ') ps1++; *ps1=*ps2; while(*ps2 !=' '){ *ps1=*ps2; ps1++;ps2++; } ps1++;ps2++; *ps1=*ps2; } int main() { char s1[100]="I LOVE YOU."; char s2[100]="And you?"; stract(s1,s2); printf("%s",s1); return 0; }
- 输出结果为 I LOVE YOU.And you?
- strcat将s1中的字符串与s2中的字符串连接到了一起
四.字符串比较strcmp
#include#include int strcmp(char* a,char* b){ char* pa=a; char* pb=b; while(*pa==*pb &&*pa!=' ' &&*pb!=' '){ pa++; pb++; } if(*pa>*pb) return 1; if(*pa<*pb) return -1; if(*pa=*pb) return 0; } int main(int argc, char *argv[]) { char a[100]="aaab"; char b[100]="aaaa"; printf("%dn",strcmp(a,b)); return 0; }
