private static async Task <HttpContent> AddNonce(FormUrlEncodedContent urlEncoded, string strNonce)
{
var list = new List <KeyValuePair <string, string> > {
KeyValuePair.Create("nonce", strNonce)
};
NameValueCollection parameters = await urlEncoded.ReadAsFormDataAsync();
for (int i = 0; i < parameters.Count; i++)
{
string[] strings = parameters.GetValues(i);
string key = parameters.GetKey(i);
if (strings?.Length != 1)
{
throw new InvalidOperationException($"For key {key} expected only one value");
}
list.Add(KeyValuePair.Create(key, strings[0]));
}
return(new FormUrlEncodedContent(list));
}