DR9885
commented
5 years ago possible example:
public class UsCensusBureauGeocoder : IGeocoder
{
private readonly int _benchmark;
private readonly HttpClient _client;
private class UsCensusBureauAddress : Address
{
private const string Key = "UsCensusBureau";
public UsCensusBureauAddress(string formattedAddress, Location coordinates)
: base(formattedAddress, coordinates, Key)
{
}
}
public UsCensusBureauGeocoder(int benchmark = 9)
{
_benchmark = benchmark;
_client = new HttpClient { BaseAddress = new Uri("https://geocoding.geo.census.gov/geocoder/") };
}
public async Task<IEnumerable<Address>> GeocodeAsync(string address)
{
// Build Query String
var queryString = HttpUtility.ParseQueryString(string.Empty);
queryString["address"] = address;
queryString["benchmark"] = "4";
queryString["format"] = "json";
// Get Request
var response = await _client.GetStringAsync($"locations/onelineaddress?" + queryString);
// Read Result
return GetAddresses(response);
}
public async Task<IEnumerable<Address>> GeocodeAsync(string street, string city, string state, string postalCode, string country)
{
// Build Query String
var queryString = HttpUtility.ParseQueryString(string.Empty);
queryString["street"] = street;
queryString["city"] = city;
queryString["state"] = state;
queryString["zip"] = postalCode;
queryString["benchmark"] = "4";
queryString["format"] = "json";
// Get Request
var response = await _client.GetStringAsync($"locations/address?" + queryString);
// Read Result
return GetAddresses(response);
}
public Task<IEnumerable<Address>> ReverseGeocodeAsync(Location location)
{
throw new NotImplementedException();
}
public Task<IEnumerable<Address>> ReverseGeocodeAsync(double latitude, double longitude)
{
throw new NotImplementedException();
}
private static IEnumerable<UsCensusBureauAddress> GetAddresses(string response)
{
var result = JObject.Parse(response)["result"];
return result["addressMatches"]
.Select(match =>
{
var formatted = match["matchedAddress"].ToString();
var coordinates = match["coordinates"];
var x = Convert.ToDouble((object) coordinates["x"]);
var y = Convert.ToDouble((object) coordinates["y"]);
return new UsCensusBureauAddress(formatted, new Location(y, x));
})
.ToArray();
}
}
There is a free api found here: https://geocoding.geo.census.gov/