json 字符串 反序列化

private void button17_Click(object sender, EventArgs e)
{
string s = "{"returnCode":0,"returnMessage":"u6210u529f","returnData":{"expect":"20190716058","opencode":"10,8,7,5,9,3,4,1,2,6"}}";
returnData data = JsonConvert.DeserializeObject<returnData>(s);
var sd = JObject.Parse(s)["returnData"];
returnData returnData = JsonConvert.DeserializeObject<returnData>(JObject.Parse(s)["returnData"].ToString());
}