ASP.NET通过ASHX返回JSON

Question

我正在为我的网站创建自动完成功能。 到目前为止，JavaScript部分已经完成。此外，我可以获取与用户匹配的MembershipUser对象。

我需要返回以下格式的JSON：

{
 query:'Li',
 suggestions:['Liberia','Libyan Arab Jamahiriya','Liechtenstein','Lithuania'],
 data:['LR','LY','LI','LT']
}

这是ashx文件中的代码：

public void ProcessRequest (HttpContext context) {
    System.Web.Script.Serialization.JavaScriptSerializer JsonSerializer;   
    string query = context.Request.QueryString["query"];
    System.Web.Security.MembershipUserCollection Users = System.Web.Security.Membership.GetAllUsers();
    context.Response.ContentType = "application/json";
    foreach (System.Web.Security.MembershipUser User in Users)
    {
        if (User.UserName.StartsWith(query.ToLower()))
        {
            context.Response.Write(query + Environment.NewLine);
            context.Response.Write(User.Email);
        }
    }
}

我如何以期望的格式返回JSON？谢谢。

- user1027620

---

顺便说一句，那不是有效的JSON。请参阅：http://json.org/ - ChaosPandion

ChaosPandion，该插件需要这个输出... :/ - user1027620

Answer 1

context.Response.Write(
    jsonSerializer.Serialize(
        new
        {
            query = "Li",
            suggestions = new[] { "Liberia", "Libyan Arab Jamahiriya", "Liechtenstein", "Lithuania" },
            data = new[] { "LR", "LY", "LI", "LT" }
        }
    )
);

- L.B

Answer 2

这是如何帮助我的：

using System;
using System.Data;
using System.Web;
using System.Linq;
using System.Collections;
using Newtonsoft.Json;

public class Handler : IHttpHandler {

public void ProcessRequest (HttpContext context) {
    context.Response.ContentType = "application/json";
    string quer = context.Request["query"];

    DataTable _t = AMC.Core.Logic.Root.Storage.ExecuteQuery("SELECT [tag_name] FROM [tags] Where [tag_name] like '%' + @ke + '%'", new System.Data.SqlClient.SqlParameter("ke", quer));

    DataRow[] list = new DataRow[_t.Rows.Count];
    _t.Rows.CopyTo(list, 0);

    var wapper = new { 
        query = quer
        , suggestions = (from row in list select row["tag_name"].ToString()).ToArray()
        //, data = new[] { "LR", "LY", "LI", "LT" } 
    };
    context.Response.Write(JsonConvert.SerializeObject(wapper));            
}

你可以在这里找到Newtonsoft.Json：http://json.codeplex.com/releases/

- BigMan

---

只是补充一下，在IE8（仅限？）中调用此代码将失败。会弹出一个对话框，询问您是否要打开或保存文件“handler.ashx”。为了解决这个问题，将代码行更改为返回文本：context.Response.ContentType =“text / html”; - Mike Gledhill

Answer 3

创建一个类，并根据你想要的返回值编写合同，然后使用JSONSerializer在该类的实例上创建你的返回内容。

[DataContract]
public class YourReturnObject {
  [DataMember(Name="query")]
  public String Query { get;set;}

  [DataMember(Name="suggestions")]
  public String[] Suggestions { get;set;}  

  [DataMember(Name="data")]
  public String[] OtherData{ get;set;} 
}

- Tim Hoolihan

---

嗨，谢谢你的回答。你能否解释一下在for循环中如何实现这个？ - user1027620

Answer 4

您的JSON格式有些不方便，因为您必须维护这两个数组的索引。我建议您使用更像这样的格式：

{
query: 'Li',
data: [{id:'LR', text:'Liberia'}, {id:'LY', text:'Libyan Arab Jamahiriya'}, ...]
}

- Al W