Yes,If we implement this function in mappoint,I think it will be hard.then,I found a websitehttp://www.infospace.com/home.toolba...es/reverse-zip,which is very good.and I can seach my most cities.
Then I program it to implement using VB.In my database,there are about 13,000 records ,and it takes about 8 hours to handle ,Oh ,No,It is too long!