C# asp.net mvc core如何返回Json查询
首先,我知道如何通过这样做返回Json查询C# asp.net mvc core如何返回Json查询,c#,json,asp.net-mvc,asp.net-core-mvc,dapper,C#,Json,Asp.net Mvc,Asp.net Core Mvc,Dapper,首先,我知道如何通过这样做返回Json查询 public JsonResult streams() { using (var conn = new NpgsqlConnection(Connectionstring)) { conn.Open(); var credentials = conn.Query<Streams>("select id,name from streams").ToList();
public JsonResult streams()
{
using (var conn = new NpgsqlConnection(Connectionstring))
{
conn.Open();
var credentials = conn.Query<Streams>("select id,name from streams").ToList();
ViewData["Message"] = "Your application description page.";
conn.Close();
return Json(credentials);
}
}
这是因为字符串中有Json,对
this.Json(object)
的调用旨在将其序列化为Json
在MVC 5中,您可以:
return this.Content(credentials, "application/json");
该类位于MVC核心中,因此我假设语法保持不变。SQL查询(在第二个示例中)结果集列是否与流属性名称匹配?您可以共享结果集吗?它没有,这是我的流名称。为什么您要从Sql查询返回json。返回正常的结果集,让Json方法负责将其转换为Json格式我的印象是,从SQL代码返回Json比在应用程序中将其转换为Json更有效,特别是在有大量请求的情况下。非常感谢,这正是我所需要的
public JsonResult streams()
{
using (var conn = new NpgsqlConnection(Connectionstring))
{
conn.Open();
var credentials = conn.Query<Streams>("SELECT array_to_json(array_agg(t)) from (select id,name from streams) t").ToList();
ViewData["Message"] = "Your application description page.";
conn.Close();
return Json(credentials);
}
}
public class Streams
{
[Key]
public int id { get; set; }
public string name { get; set; }
public int profile_id { get; set; }
public DateTime created_on { get; set; }
public int last_reply { get; set; }
public int comments { get; set; }
public string city { get; set; }
public string state { get; set; }
public float latitudes { get; set; }
public float longitudes { get; set; }
public int votes { get; set; }
}
return this.Content(credentials, "application/json");