c# - DateTime Format Handling -

i have program has synchronization. means need save last synchronization date , check if needs synchronized.

so, have this:

is.savecontactsretrievedate(datetime.now.tostring("dd.mm.yyyy")); 

saving date isolated storage.

then, when call if:

datetime todate = datetime.now;  string contactsretrivedate = is.readcontactsretrivedate(); if (contactsretrivedate == "" || datetime.compare(todate, datetime.parse(contactsretrivedate)) == 1) {     messagebox.show(""); } 

the problem when user changes region code fails here:

datetime.compare(todate, datetime.parse(contactsretrivedate)) 

with incorrect input error.

i understand latvian format dd.mm.yyyy , usa mm/dd/yyyy - can't find solution...

i need datetime parsed in 1 format, add days, weeks , compare date.

you can use parseexact

datetime.parseexact(datestring, "dd.mm.yyyy", system.globalization.cultureinfo.invariantculture); 

you know format can go this, make sure string in same format , never changes.