#include <stdio.h> #include <wctype.h> int main () { int i; wchar_t str[] = L"c3po..."; i=0; while (iswalnum(str[i])){ i++; } wprintf (L"The first %d characters are alphanumeric.\n",i); return 0; }
输出
The first 4 characters are alphanumeric.
原文：https://www.cnblogs.com/sea-stream/p/10822183.html