Anyone who have used Paypal connect integration? Paypal connect, that is used to get Client or customer information?

问题

I want to Use Paypal Connect API using Connect With PayPal Integrate https://developer.paypal.com/docs/connect-with-paypal/integrate/ Anyone who has done it before because I am having such errors.

I have integrate this Successfully till 5th step, but here in 6th step I cant hit API successfully

This is my request:

Method: POST, RequestUri: 'https://api.sandbox.paypal.com/v1/oauth2/token?grant_type=authorization_code&code={CodeProvided}', Version: 1.1, Content: , Headers: { Authorization: Basic {clientId}:{secret} }

and this is the error i got:

{"error":"invalid_client","error_description":"Client Authentication failed"}

This snippet of my code:

HttpClient client = new HttpClient();

client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", $"{clientId}:{clientSecret}");

HttpResponseMessage response =  client.PostAsync($"https://api.sandbox.paypal.com/v1/oauth2/token?grant_type=authorization_code&code={code}",null).Result;

and this is the URL that i got:

https://www.example.com/Home/PaypalAuth?code=C21AAFXblx1g8x1ryZfCh6fIEesnuQ-47B3ObeF3toP50oYfUoqfCyZ8l6Yet9rRJ2E9RJfl-kDhzS9Xsw1LJVm8w5pblpqiw&scope=openid

However, I have also changed my secret and client id to base64 and checked but couldn't get desired response.

I have also added = at last to auhtentication for checking still it returns error.

I have also set body with json and put it as content in post content instead of null. like this:

ConnectPaypalBody body = new ConnectPaypalBody();
body.code = code;
body.grant_type = "authorization_code";

var json = JsonConvert.SerializeObject(body);
var data = new StringContent(json, Encoding.UTF8, "application/json");

HttpResponseMessage response =  client.PostAsync($"https://api.sandbox.paypal.com/v1/oauth2/token?grant_type=authorization_code&code={code}",data).Result;

来源：https://stackoverflow.com/questions/61479783/anyone-who-have-used-paypal-connect-integration-paypal-connect-that-is-used-to