Some markdown 📝.

Author: Kevin Hellemun

BunqSdk/Exception/EXCEPTIONS.md

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+## Exceptions
+
+When you make a request via the SDK, there is a chance of request failing
+due to various reasons. When such a failure happens, an exception
+corresponding to the error occurred is raised.
+
+
+----
+#### Possible Exceptions
+
+* `BadRequestException` If the request returns with status code `400`
+* `UnauthorizedException` If the request returns with status code `401`
+* `ForbiddenException` If the request returns with status code `403`
+* `NotFoundException` If the request returns with status code `404`
+* `MethodNotAllowedException` If the request returns with status code `405`
+* `TooManyRequestsException` If the request returns with status code `429`
+* `PleaseContactBunqException` If the request returns with status code `500`.
+If you get this exception, please contact us preferably via the support chat in the bunq app.
+* `UnknownApiErrorException` If none of the above mentioned exceptions are raised,
+this exception will be raised instead.
+
+For more information regarding these errors, please take a look on the documentation
+page here: https://doc.bunq.com/api/1/page/errors
+
+---
+#### Base exception
+All the exceptions have the same base exception which looks like this:
+```c#
+   public class ApiException : System.Exception
+    {
+        private readonly string message;
+        public int ResponseCode { get;}
+
+        public override string Message
+        {
+            get { return message; }
+        }
+
+        /// <param name="responseCode">The HTTP Response code of the failed request.</param>
+        /// <param name="message">The list of messages related to this exception.</param>
+        public ApiException(int responseCode, string message) : base(message)
+        {
+        }
+    } 
+```
+This means that each exception will have the response code and the error message 
+related to the specific exception that has been raised.
+
+---
+#### Exception handling
+Because we raise different exceptions for each error, you can catch an error
+if you expect it to be raised.
+
+```c#
+using Bunq.Sdk.Context;
+using Bunq.Sdk.Exception;
+
+public class BadRequest
+{
+    private const string API_KEY = "Some invalid API key"
+    private const string DESCRIPTION = "This will throw BadRequestException."
+    
+    public void Run()
+    {
+        try
+        {
+            ApiContext.Create(ApiEnvironmentType.SANDBOX, API_KEY, DEVICE_DESCRIPTION);
+        }
+        catch(BadRequestException error)
+        {
+            Console.WriteLine(error.getMessage())
+            Console.WriteLine(error.getResponseCode())
+        }
+    }
+}
+```
+
+This will ensure that you are ready for anything that might go wrong!