HttpClient client = new HttpClient();
//使用FormUrlEncodedContent做HttpContent
var cOntent= new FormUrlEncodedContent(new Dictionary<string, string>()
{
{ "q", name},
{ "from", "zh"},
{ "to", "en"}
});
var respOnse= await client.PostAsync(url, content);
var result = await response.Content.ReadAsAsync();