public ReadOnlyCollection<Document> Save(string file, string title, string tags = null, long? captchaSid = null, string captchaKey = null)
{
VkErrors.ThrowIfNullOrEmpty(() => file);
VkErrors.ThrowIfNullOrEmpty(() => title);
var responseJson = JObject.Parse(file);
file = responseJson["file"].ToString();
var parameters = new VkParameters
{
{ "file", file },
{ "title", title },
{ "tags", tags },
{ "captcha_sid", captchaSid },
{ "captcha_key", captchaKey }
};
var response = _vk.Call("docs.save", parameters);
return response.ToReadOnlyCollectionOf<Document>(r => r);
}