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.NET
The what3words Free API plan will no longer include convert-to-coordinate requests. To continue using this feature, please upgrade to one of our paid plans starting from £7.99/month. Learn more about our API plans here.
As a reminder, emergency services can make use of the what3words API for free, and we have a dedicated plan for NGOs and registered charities. If your organisation falls within these categories, please get in touch. For any questions or assistance, feel free to reach out to support@what3words.com.
The .NET API wrapper is useful for .NET developers who wish to seamlessly integrate the what3words API into their applications, without the hassle of having to manage the low level API calls themselves.
A full example of how to integrate the what3words .NET wrapper is available in our
.NET Github repository
The artifact is available through NuGet Package what3words.dotnet.wrapper.
dotnet add package what3words.dotnet.wrapper
Use the What3WordsV3
using What3WordsV3;
Instantiate an instance of What3WordsV3, from which all API requests can be made
var wrapper = new What3WordsV3("YOUR_API_KEY_HERE");
If you run our Enterprise Suite API Server yourself, you may specify the URL to your own server like so:
var wrapper = new What3Words("YOUR_API_KEY_HERE", "https://api.yourserver.com")
Convert to what3words address
This function converts coordinates (expressed as latitude and longitude) to a what3words address.
More information about ConvertTo3wa
, including returned results is available in the what3words REST API documentation.
Find the words for (51.222011, 0.152311
):
var result = await wrapper.ConvertTo3WA(new Coordinates(51.222011, 0.152311)).RequestAsync();
Convert to coordinates
This function converts a what3words address to a position, expressed as coordinates of latitude and longitude.
It takes the words parameter as a string of a what3words 'table.book.chair'
More information about ConvertToCoordinates
, including returned results is available in the what3words REST API documentation.
Find the words for ///filled.count.soap
:
var result = await wrapper.ConvertToCoordinates("filled.count.soap").RequestAsync();
AutoSuggest
When presented with a what3words address which may be incorrectly entered, AutoSuggest returns a list of potential correct 3 word addresses. It needs the first two words plus at least the first character of the third word to produce suggestions.
This method provides corrections for mis-typed words (including plural VS singular), and words being in the wrong order.
Optionally, clipping can narrow down the possibilities, and limit results to:
- One or more countries
- A geographic area (a circle, box or polygon)
This dramatically improves results, so we recommend that you use clipping if possible.
To improve results even further, set the focus
to user’s current location. This will make AutoSuggest
return results which are closer to the user.
More information about AutoSuggest
, including returned results is available in the what3words REST API documentation.
Code example Simple basic call:
var result = await wrapper.Autosuggest("index.home.r").RequestAsync();
Code example AutoSuggest, clipping the results returned to the United Kingdom and Belgium:
var result = await wrapper.Autosuggest("index.home.r", new AutosuggestOptions().ClipToCircle('GB,BE')).RequestAsync();
Code example AutoSuggest, Focus on (51.4243877,-0.34745
).
var result = await wrapper.Autosuggest("index.home.r", new AutosuggestOptions().SetFocus(51.4243877,-0.34745)).RequestAsync();
Code example AutoSuggest, with Generic Voice input type.
var result = await wrapper.Autosuggest("fun with code", new AutosuggestOptions().InputType('generic-voice').RequestAsync();
Grid section
Grid section returns a section of the what3words 3m x 3m grid as a set of horizontal and vertical lines covering the requested area, which can then be drawn onto a map.
The requested box must not exceed 4km from corner to corner, or a BadBoundingBoxTooBig
error will be returned.
More information about GridSection
, including returned results is available in the what3words REST API documentation.
Get a grid for (51.222609, 0.152898
) in the south-west, and (51.222011, 0.152311
in the north-east:
var result = await wrapper.GridSection(new Coordinates(51.222011, 0.152311), new Coordinates(51.222609, 0.152898)).RequestAsync();
Available languages
This function returns the currently supported languages. It will return the two letter code, and the name of the language both in that language and in English.
More information about AvailableLanguages
, including returned results is available in the what3words REST API documentation.
var result = await wrapper.AvailableLanguages().RequestAsync();
Handling errors
Success or failure of an API call can be determined through the use of the IsSuccessful
propriety.
If it’s been determined that an API call was not successful, Error
type and Message
values which represent the error, are accessible from through the Error
propriety.
var autosuggestResult = await api.Autosuggest( "freshen.overlook.clo", new AutosuggestOptions().SetClipToCountry(new List<string> { "fr", "de" }) ).RequestAsync(); if (autosuggestResult.IsSuccessful) { ... } else { if (autosuggestResult.Error.Error == What3WordsError.BadClipToCountry) { // Invalid country clip is provided Console.WriteLine($"BadClipToCountry: {autosuggestResult.Error.Message}"); } }
This section introduces RegEx functions that can assist with checking and finding possible what3words addresses in strings. The three main functions covered are:
isPossible3wa
– Match what3words address format;findPossible3wa
– Find what3words address in Text;isValid3wa
– Verify a what3words address with the API;
isPossible3wa
Our API wrapper RegEx function “isPossible3wa
” can be used used to detect if a text string (like “filled.count.soap
“) in the format of a what3words address without having to ask the API. This functionality checks if a given string could be a what3words address. It returns true if it could be, otherwise false.
Note: This function checks the text format but not the validity of a what3words address. Use isValid3wa
to verify validity.
using System; using what3words.dotnet.wrapper; namespace What3WordsExample { class Program { static void Main(string[] args) { // Initialize the What3Words API with your API key var api = new What3WordsV3("YOUR_API_KEY"); // Example what3words addresses string[] addresses = { "filled.count.soap", "not a 3wa", "not.3wa address" }; // Check if the addresses are possible what3words addresses foreach (var address in addresses) { bool isPossible = api.IsPossible3wa(address); Console.WriteLine($"Is '{address}' a possible what3words address? {isPossible}"); } } } }
Expected Output
- isPossible3wa(“filled.count.soap”) returns
true
- isPossible3wa(“not a 3wa”) returns
false
- isPossible3wa(“not.3wa address”)returns
false
findPossible3wa
Our API wrapper RegEx function “findPossible3wa
” can be used to detect a what3words address within a block of text, useful for finding a what3words address in fields like Delivery Notes
. For example, it can locate a what3words address in a note like “Leave at my front door ///filled.count.soap
”. The function will match if there is a what3words address within the text. If no possible addresses are found, it returns an empty list.
Note:
- This function checks the text format but not the validity of a what3words address. Use
isValid3wa
to verify validity. - This function is designed to work across languages but do not work for
Vietnamese (VI)
due to spaces within words.
using System; using what3words.dotnet.wrapper; namespace What3WordsExample class Program { static void Main(string[] args) { // Initialize the what3words API with your API key var api = new What3WordsV3("YOUR_API_KEY"); // Example texts string[] texts = { "Please leave by my porch at filled.count.soap", "Please leave by my porch at filled.count.soap or deed.tulip.judge", "Please leave by my porch at" }; // Check each text for possible what3words addresses foreach (var text in texts) { List<string> possibleAddresses = api.FindPossible3wa(text); Console.WriteLine($"Possible what3words addresses in '{text}': {string.Join(", ", possibleAddresses)}"); } } }
Expected Output
- findPossible3wa(“Please leave by my porch at filled.count.soap”) returns
['filled.count.soap']
- findPossible3wa(“Please leave by my porch at filled.count.soap or deed.tulip.judge”) returns
['filled.count.soap', 'deed.tulip.judge']
- findPossible3wa(“Please leave by my porch at”) returns
[]
isValid3wa
Our API wrapper RegEx function “isValid3wa
” can be used to determine if a string is a valid what3words address by checking it against the what3words RegEx filter and verifying it with the what3words API.
using System; using what3words.dotnet.wrapper; namespace What3WordsExample class Program { static void Main(string[] args) { // Initialize the what3words API with your API key var api = new What3WordsV3("YOUR_API_KEY"); // Example addresses string[] addresses = { "filled.count.soap", "filled.count.", "coding.is.cool" }; // Check if the addresses are valid what3words addresses foreach (var address in addresses) { bool isValid = api.IsValid3wa(address); Console.WriteLine($"Is '{address}' a valid what3words address? {isValid}"); } } }
Expected Outputs
- isValid3wa(“filled.count.soap”) returns
True
- isValid3wa(“filled.count.”) returns
False
- isValid3wa(“coding.is.cool”) returns
False
Also make sure to replace <YOUR_API_KEY>
with your actual API key. These functionalities provide different levels of validation for what3words addresses, from simply identifying potential addresses to verifying their existence on Earth.
If you encounter errors or issues related to convert-to-coordinate requests while using the Free plan, please check the network panel for the following error message Error 402 payment required
and its response, indicating the need to upgrade to a higher plan:
{ "error": { "code": "QuotaExceeded", "message": "Quota Exceeded. Please upgrade your usage plan, or contact support@what3words.com" } }
For more information, visit our API plans page. If you need further assistance, contact support@what3words.com.