Using RestSharp (C#) to update module records


I'm trying to use RestSharp to connect to our SugarCRM REST API to update a record in the Opportunities module. I used the support page on /module/:record PUT and the PHP example to determine the right syntax for building my RestRequest, however I keep ending up with a StatusCode 422, indicating an invalid parameter.

I set up the C# code below to change the record's name, after succesfully acquiring the access token in a separate method ('_accessToken') and the Opportunity record that needs changing ('SugarProject'):

public bool SetProjectName(SugarProject project)
var values = new Dictionary<string, string>();
values.Add("name", "Test");

var request = new RestRequest("Opportunities/{id}", Method.PUT);

request.AddUrlSegment("id", project.Id); // Set the record's UUID in the URL
request.AddHeader("Cache-Control", "no-cache");
request.AddParameter("OAuth-Token", _accessToken); // Use access token acquired earlier

// request.AddJsonBody(values); // Scenario 1: Tried converting to JSON directly from a Dictionary class
request.AddJsonBody(new { name = "Test" }); // Scenario 2: Tried creating the JSON object manually
// request.AddParameter("name", "Test", ParameterType.RequestBody); // Scenario 3: Tried using RestSharp's built-in way to add a parameter without doing any JSON conversion
var response = _client.Execute(request);
return response.IsSuccessful;

The parameter stored in the RestRequest's 'Parameters' property look as follows in each scenario:

  1. {application/json={"name":"Test"}}
  2. {application/json={"name":"Test"}}
  3. {name=Test}

The cURL command below successfully changes the Opportunity's name to 'Test' when I pause the C# code during debugging and use the access token from _accessToken. This leads me to believe all is well in the code above, except for the string containing the record field that needs changing, and its new value.

curl -X PUT -H OAuth-Token:*_accessToken* -H Cache-Control:no-cache -d '{"name":"Test"}' https://*SugarCRM URL*/rest/v10/Opportunities/4faab519-bea0-37b0-a3f9-5810bfa3dea6

Any help would be much appreciated!

Kind regards,