Get Timezone Offset From City and State/Province or Zip

问题

I have an asp.net website that will be hosted on a server using EST time and will likely be made on a computer/device operating in EST. The user will be making updates to information pertaining to locations all over North America. I need the timestamp of the update to be made in the local time of the location that the update is being made to, not server or computer time. So I need to be able to get the offset for a location based on either City and State/Province or the Zip code. I've already looked at http://www.earthtools.org/webservices.htm#timezone and it requires latitude and longitude, which I don't have.

回答1:

You can retireve Latitude and Longitude from Google map.

For example, address is '123 Street, Los Angeles, CA 12345' or address is zip code only '12346'

public void GetCoordinate(string address)
{
    WebClient client = new WebClient();
    Uri uri = new Uri(String.Format("http://maps.google.com/maps/geo?output=csv&q=" + HttpUtility.UrlEncode(address)));

    // Return numbers -
    // 1 = Status Code
    // 2 = Accurancy
    // 3 = Latitude
    // 4 = Longitude
    string[] geocodeInfo = client.DownloadString(uri).Split(',');

    decimal latitude = Convert.ToDecimal(geocodeInfo[2]);                
    decimal longitude = Convert.ToDecimal(geocodeInfo[3]);            
}

I suggest save the created/updated time in UTC. When you display it, convert that UTC to user's local time based on the user's time zone offset (which is saved in the user's profile).

来源：https://stackoverflow.com/questions/8842153/get-timezone-offset-from-city-and-state-province-or-zip

标签

ASP.NET

api

timezone