external(INT, "SystemTimeToVariantTime", "SystemTimeToVariantTime", "OleAut32.dll");

int difference;
int result=date_compare("07.10.2019", "07.10.2020", #difference);
messagebox("Дней между датами: "+format(difference));
if(result==-1)messagebox("Ошибка");
if(result==0)messagebox("Даты равны");
if(result==1)messagebox("Первая дата больше");
if(result==2)messagebox("Вторая дата больше");


function date_compare(string d1, string d2, int #difference_day)
{
char st[16], st2[16];
double x, x2;
string s1[3], s2[3];
int count1=regexsearch(3, #s1[0], d1, "\d+");
int count2=regexsearch(3, #s2[0], d2, "\d+");
if(count1==3 && count2==3)
{
struct_systemtime(#st[0], s1[0], s1[1], s1[2]);
struct_systemtime(#st2[0], s2[0], s2[1], s2[2]);
SystemTimeToVariantTime(address(#st[0]), address(#x));
SystemTimeToVariantTime(address(#st2[0]), address(#x2));
difference_day=sqrt(pow(x2-x, 2));
if(x==x2)return 0;
if(x>x2)return 1;
if(x<x2)return 2;
}
difference_day=-1;
return -1;
}

function struct_systemtime(char #systemtime, string day, string month, string year)
{
initialarray(#systemtime[0], 0);
codhex(formatsn(year), #systemtime[0]);
codhex(formatsn(month), #systemtime[2]);
codhex(formatsn(day), #systemtime[6]);
}