尝试将请求类切换到其他类。
例如,您可以使用HttpClient
var clientId = "yyyy";
var secret = "xxxx";
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("https://api-m.sandbox.paypal.com/");
var authToken = Convert.ToBase64String(Encoding.UTF8.GetBytes($"{clientId}:{secret}"));
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", authToken);
var requestContent = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("grant_type", "client_credentials")
});
var response = await client.PostAsync("v1/oauth2/token", requestContent);
response.EnsureSuccessStatusCode();
var responseBody = await response.Content.ReadAsStringAsync();
}