将LINQ查询结果存储为JSON对象并传递给javascript

Question

我有添加到列表中的查询。现在我需要在javascript中使用它。它正在ASP.NET 3.5中完成。所以，我需要将它作为JSON对象发送。这是我做了什么：（我不知道这是否是得到一个JSON对象的正确的方法纠正我，如果我错了

List<NCDCPoint> dupli = (from n in CDC.NCDCPoints 
          where n.EVENT_TYPE_ID == et 
          where n.BeginDate == b 
          where n.EndDate == e 
          select n).ToList<NCDCPoint>(); 
    System.Web.Script.Serialization.JavaScriptSerializer oSerializer = 
new System.Web.Script.Serialization.JavaScriptSerializer(); 
    string sJSON = oSerializer.Serialize(dupli); 





} 

这是我的jQuery的样子

$.ajax({ 
      type: "POST", url: "Data.aspx/CheckInsertRecord", 
      data: "{EventType:'" + eventtype + "',BeginDate:'" + begindate + "'," + 
        "EndDate:'" + enddate+"' }", 
      contentType: "application/json; charset=utf-8", dataType: "json", 
      success: function (msg) { 
      alert(msg.d); 
      if(msg.d == "true") 
     { 
     Showduplicate(); 
     } 
      } 
     }); 

。

所以，请让我知道接下来我需要做什么？还有一件事是我已经返回true或false返回到aspx页面中的$ .ajax {}那么我应该如何发送JSON对象？

Answer 1

如果您刚刚开始使用，那么从一开始就最好使用ASP.NET MVC，它比传统的ASP.NET Web更好形式。当你这样做时，你想创建一个返回JsonResult的操作方法。这里有一篇很好的文章让你开始。

http://msmvps.com/blogs/shahed/archive/2009/08/23/asp-net-asp-net-mvc-tips-json-handler-aspx-template-asynchronous-jquery-treeview-with-ashx-generic-handler-and-many-more.aspx

Answer 2

更改方法返回List<NCDCPoint>和声明的返回类型为JSON：

[WebMethod] 
[ScriptMethod(ResponseFormat = ResponseFormat.Json] 
public static List<NCDCPoint> CheckInsertRecord(String EventType, String BeginDate, String EndDate) 
{ 
    NCDCPoint ncdc = new NCDCPoint(); 
    CEOSurveyDataContext CDC = new CEOSurveyDataContext(); 
    int et = Convert.ToInt32(EventType); 


    DateTime b = Convert.ToDateTime(BeginDate); 
    DateTime e = Convert.ToDateTime(EndDate); 

     bool query = (from n in CDC.NCDCPoints 
         where n.EVENT_TYPE_ID == et 
         where n.BeginDate == b 
         where n.EndDate == e 
         select n).Count()>0; 

    return = (from n in CDC.NCDCPoints 
          where n.EVENT_TYPE_ID == et 
          where n.BeginDate == b 
          where n.EndDate == e 
          select n).ToList<NCDCPoint>(); 
} 

Answer 3

可以使用JavascriptSerializer serailize对象，并将其发送。

var dupli= from n in CDC.NCDCPoints 
         where n.EVENT_TYPE_ID == et 
         where n.BeginDate == b 
         where n.EndDate == e 
         select n; 

return new JavaScriptSerializer().Serialize(dupli); 

而在jquery ajax的成功回调。

... 
success:function(msg){ 
var data = $.parseJSON(msg.d); 
//And you get your object 
}