將LINQ查詢結果存儲爲JSON對象並傳遞給javascript

Question

我有添加到列表中的查詢。現在我需要在javascript中使用它。它正在ASP.NET 3.5中完成。所以，我需要將它作爲JSON對象發送。這是我做了什麼：（我不知道這是否是得到一個JSON對象的正確的方法糾正我，如果我錯了

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); 





} 

這是我的jQuery的樣子

$.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，請讓我知道接下來我需要做什麼？還有一件事是我已經返回true或false返回到aspx頁面中的$ .ajax {}那麼我應該如何發送JSON對象？

Answer 1

如果您剛剛開始使用，那麼從一開始就最好使用ASP.NET MVC，它比傳統的ASP.NET Web更好形式。當你這樣做時，你想創建一個返回JsonResult的操作方法。這裏有一篇很好的文章讓你開始。

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>和聲明的返回類型爲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對象，並將其發送。

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的成功回調。

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