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How can I use a string argument to case a namespace or type?

由 不羁的心 提交于 2020-01-14 07:24:11

问题


I need to get some JSON output in a .NET 2.0 C# script. The goal is to use one method to output all the JSON feeds I need. All the models have the same id and name properties so I have about 15 namespaces that have the same parts here. In short: since I'm use castle I can call the function like:

/public/get_place_tags.castle
/public/get_place_types.castle
/public/get_place_whichEver.castle

Which in castle is calling each method, ie: the get_place_tags(){} but I want to not have to work where I can call one method to get output from each type like this:

/public/get_json.castle?wantedtype=place_types

Does anyone know how to fix this?

namespace campusMap.Controllers
{
    [Layout("home")]
    public class PublicController : BaseController
    {
        /*  works and returns */
        public void get_pace_type()
        {
            CancelView();
            CancelLayout();

            place_types[] types = ActiveRecordBase<place_types>.FindAll();
            List<JsonAutoComplete> type_list = new List<JsonAutoComplete>();

            foreach (place_types place_type in types)
            {
                JsonAutoComplete obj = new JsonAutoComplete();

                obj.id = place_type.place_type_id;
                obj.label = place_type.name;
                obj.value = place_type.name;

                type_list.Add(obj);
            }

            string json = JsonConvert.SerializeObject(type_list);
            RenderText(json);
        }

        /*  can;t ever find the namespace */
        public void get_json(string wantedtype)
        {
            CancelView();
            CancelLayout();
            Type t = Type.GetType(wantedtype); 

            t[] all_tag = ActiveRecordBase<t>.FindAll();
            List<JsonAutoComplete> tag_list = new List<JsonAutoComplete>();

            foreach (t tag in all_tag)
            {
                JsonAutoComplete obj = new JsonAutoComplete();

                obj.id = tag.id;
                obj.label = tag.name;
                obj.value = tag.name;

                tag_list.Add(obj);
            }

            string json = JsonConvert.SerializeObject(tag_list);
            RenderText(json);
        }
    }
}

[EDIT]-- (Newest Idea) Runtime type creation.. This I think is the cleanest idea on a way to get it to work...-----

So the goal is really to have at runtime a type used.. right.. so I thought this would work. http://www.java2s.com/Code/CSharp/Development-Class/Illustratesruntimetypecreation.htm and based of that here is the method so far. I'm still having issues getting t to get past the error "The type or namespace name 't' could not be found (are you missing a using directive or an assembly reference?)" .. not sure where I'm going wrong here. Can't seem to get any of it to work lol.. 

public void get_json(String TYPE)
{
    CancelView();
    CancelLayout();
    if (String.IsNullOrEmpty(TYPE))
    {
        TYPE = "place_types";
    }
    // get the current appdomain
    AppDomain ad = AppDomain.CurrentDomain;

    // create a new dynamic assembly
    AssemblyName an = new AssemblyName();
    an.Name = "DynamicRandomAssembly";
    AssemblyBuilder ab = ad.DefineDynamicAssembly(an, AssemblyBuilderAccess.Run);

    // create a new module to hold code in the assembly
    ModuleBuilder mb = ab.DefineDynamicModule("RandomModule");

    // create a type in the module
    TypeBuilder tb = mb.DefineType(TYPE, TypeAttributes.Public);

    // finish creating the type and make it available
    Type t = tb.CreateType();
    t[] all_tag = ActiveRecordBase<t>.FindAll();

    List<JsonAutoComplete> tag_list = new List<JsonAutoComplete>();
    foreach (t tag in all_tag)
    {
        JsonAutoComplete obj = new JsonAutoComplete();
        obj.id = tag.id;
        obj.label = tag.name;
        obj.value = tag.name;
        tag_list.Add(obj);
    }
    RenderText(JsonConvert.SerializeObject(tag_list)); 
}

[EDIT]-- (Older idea) Eval code-----

So this attempt to make this happen is to use reflection and stuff to do a eval of sorts based on this http://www.codeproject.com/script/Articles/ViewDownloads.aspx?aid=11939

namespace EvalCSCode
{
    /// <summary>
    /// Interface that can be run over the remote AppDomain boundary.
    /// </summary>
    public interface IRemoteInterface
    {
        object Invoke(string lcMethod, object[] Parameters);
    }


    /// <summary>
    /// Factory class to create objects exposing IRemoteInterface
    /// </summary>
    public class RemoteLoaderFactory : MarshalByRefObject
    {
        private const BindingFlags bfi = BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance;

        public RemoteLoaderFactory() { }

        /// <summary> Factory method to create an instance of the type whose name is specified,
        /// using the named assembly file and the constructor that best matches the specified parameters. </summary>
        /// <param name="assemblyFile"> The name of a file that contains an assembly where the type named typeName is sought. </param>
        /// <param name="typeName"> The name of the preferred type. </param>
        /// <param name="constructArgs"> An array of arguments that match in number, order, and type the parameters of the constructor to invoke, or null for default constructor. </param>
        /// <returns> The return value is the created object represented as ILiveInterface. </returns>
        public IRemoteInterface Create(string assemblyFile, string typeName, object[] constructArgs)
        {
            return (IRemoteInterface)Activator.CreateInstanceFrom(
                assemblyFile, typeName, false, bfi, null, constructArgs,
                null, null, null).Unwrap();
        }
    }
}


#endregion
namespace campusMap.Controllers
{

    public class JsonAutoComplete
    {
        private int Id;
        [JsonProperty]
        public int id
        {
            get { return Id; }
            set { Id = value; }
        }
        private string Label;
        [JsonProperty]
        public string label
        {
            get { return Label; }
            set { Label = value; }
        }
        private string Value;
        [JsonProperty]
        public string value
        {
            get { return Value; }
            set { Value = value; }
        }
    }


    [Layout("home")]
    public class publicController : BaseController
    {
        #region JSON OUTPUT
        /*  works and returns */
        public void get_pace_type()
        {
            CancelView();
            CancelLayout();
            place_types[] types = ActiveRecordBase<place_types>.FindAll();

            List<JsonAutoComplete> type_list = new List<JsonAutoComplete>();
            foreach (place_types place_type in types)
            {
                JsonAutoComplete obj = new JsonAutoComplete();
                obj.id = place_type.id;
                obj.label = place_type.name;
                obj.value = place_type.name;
                type_list.Add(obj);
            }
            string json = JsonConvert.SerializeObject(type_list);
            RenderText(json);
        }
        /*  how I think it'll work to have a dynmaic type */
        public void get_json(string type)
        {
            CancelView();
            CancelLayout();
            /*t[] all_tag = ActiveRecordBase<t>.FindAll();

            List<JsonAutoComplete> tag_list = new List<JsonAutoComplete>();
            foreach (t tag in all_tag)
            {
                JsonAutoComplete obj = new JsonAutoComplete();
                obj.id = tag.id;
                obj.label = tag.name;
                obj.value = tag.name;
                tag_list.Add(obj);
            }*/
            StringBuilder jsonobj = new StringBuilder("");
            jsonobj.Append(""+type+"[] all_tag = ActiveRecordBase<"+type+">.FindAll();\n");
            jsonobj.Append("List<JsonAutoComplete> tag_list = new List<JsonAutoComplete>();{\n");
            jsonobj.Append("foreach ("+type+" tag in all_tag){\n");
            jsonobj.Append("JsonAutoComplete obj = new JsonAutoComplete();\n");
            jsonobj.Append("obj.id = tag.id;\n");
            jsonobj.Append("obj.label = tag.name;\n");
            jsonobj.Append("obj.value = tag.name;\n");
            jsonobj.Append("tag_list.Add(obj);\n");
            jsonobj.Append("}\n");

            CSharpCodeProvider c = new CSharpCodeProvider();
            ICodeCompiler icc = c.CreateCompiler();
            CompilerParameters cp = new CompilerParameters();

            cp.ReferencedAssemblies.Add("system.dll");
            cp.ReferencedAssemblies.Add("Newtonsoft.Json.Net20.dll");
            cp.ReferencedAssemblies.Add("Castle.ActiveRecord.dll");

            cp.CompilerOptions = "/t:library";
            cp.GenerateInMemory = true;

            StringBuilder sb = new StringBuilder("");
            sb.Append("namespace CSCodeEvaler{ \n");
            sb.Append("public class CSCodeEvaler{ \n");
            sb.Append("public object EvalCode(){\n");
            sb.Append("return " + jsonobj + "; \n");
            sb.Append("} \n");
            sb.Append("} \n");
            sb.Append("}\n");

            CompilerResults cr = icc.CompileAssemblyFromSource(cp, sb.ToString());
            System.Reflection.Assembly a = cr.CompiledAssembly;
            object o = a.CreateInstance("CSCodeEvaler.CSCodeEvaler");

            Type t = o.GetType();
            MethodInfo mi = t.GetMethod("EvalCode");

            object s = mi.Invoke(o, null); 

            string json = JsonConvert.SerializeObject(s);
            RenderText(json);
        }/**/
        #endregion
   }

I know it was suggested that the using is not needed.. I know I don't know them off the top and maybe that is level showing.. But here they are for what I think will work just above.

using System;
using System.Collections;
using System.Collections.Generic;
using Castle.ActiveRecord;
using Castle.ActiveRecord.Queries;
using Castle.MonoRail.Framework;
using Castle.MonoRail.ActiveRecordSupport;
using campusMap.Models;
using MonoRailHelper;
using System.IO;
using System.Net;
using System.Web;
using NHibernate.Expression;
using System.Xml;
using System.Xml.XPath;
using System.Text.RegularExpressions;
using System.Text;
using System.Net.Sockets;
using System.Web.Mail;
using campusMap.Services;


using Newtonsoft.Json;
using Newtonsoft.Json.Utilities;
using Newtonsoft.Json.Linq;

using System.CodeDom;
using System.CodeDom.Compiler;
using System.Reflection;
using Microsoft.CSharp;
using System.Reflection.Emit;
using System.Runtime.InteropServices;
using System.Runtime.Remoting;
using System.IO;
using System.Threading;
using System.Reflection;

回答1:


OK, this is just a suggestion, and I know nothing about castle but it seems to me that you are wanting a custom route.

This is untested and of course you will have to tweak it but have a look at your Global.asax RegisterRoutes method and add this above you default route

        routes.MapRoute(
            "TypeRoute", // Route name
            "Public/{wantedtype}", // URL with parameters
            new { controller = "Public", action = "get_json", wantedtype = UrlParameter.Optional } // Parameter defaults
        );

something like this might get what you are after.

you might need to fiddle with the action so it matches your castle framework

EDIT

I had some more time to look at this. Using the route I described above and the following method on the controller I got a good result

    public void get_json(string wantedtype)
    {
        Type t = Type.GetType(wantedtype);
        // t.Name = "Int32" when "System.Int32 is used as the wanted type
    }

http://.../Public/System.Int32 works, this url doesn't work http://.../Public/Int32

Now if you wanted to use the short version you could use something like MEF or AutoFAC or Castle to do a lookup in your container for the type you are after.

So my answer is use a good route to get the key for the wanted type then build a factory to manage the type mappings and produce an instance of what you are after.




回答2:


I just had a look at the ActiveRecord API Doco Here

There is a method FindAll(Type targetType) : Array

have you tried replacing 

 Type t = Type.GetType(wantedtype); 
 t[] all_tag = ActiveRecordBase<t>.FindAll();
 // blah blah blah

with 

Type t = Type.GetType(wantedtype); 
dynamic all_tag = ActiveRecordBase.FindAll(t);
RenderText(JsonConvert.SerializeObject(all_tag ));

completely untested but see what you think




回答3:


I tired and tried and tired to so one of these ways. Me and an co-worker came up this with solution. I made 2 files.

Ijson_autocomplete.cs

using System;
namespace campusMap.Models
{
    public interface Ijson_autocomplete
    {
        int id { get; set; }
        string name { get; set; }
        String get_json_data();
    }
}

json_autocomplete.cs

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using Castle.ActiveRecord;
using System.Collections.Generic;
using System.Data.SqlTypes;
using Newtonsoft.Json;
using Newtonsoft.Json.Utilities;
using Newtonsoft.Json.Linq;



namespace campusMap.Models
{

    public class JsonAutoComplete
    {
        private int Id;
        [JsonProperty]
        public int id
        {
            get { return Id; }
            set { Id = value; }
        }
        private string Label;
        [JsonProperty]
        public string label
        {
            get { return Label; }
            set { Label = value; }
        }
        private string Value;
        [JsonProperty]
        public string value
        {
            get { return Value; }
            set { Value = value; }
        }
    }
    public class json_autocomplete<t> where t : campusMap.Models.Ijson_autocomplete
    {

        virtual public String get_json_data()
        {
            t[] all_tag = ActiveRecordBase<t>.FindAll();
            List<JsonAutoComplete> tag_list = new List<JsonAutoComplete>();
            foreach (t tag in all_tag)
            {
                JsonAutoComplete obj = new JsonAutoComplete();
                obj.id = tag.id;
                obj.label = tag.name;
                obj.value = tag.name;
                tag_list.Add(obj);
            }
            return JsonConvert.SerializeObject(tag_list);
        }
    }
}

then when I called the function from the url this is what it ended up as

        public void get_json(String TYPE)
        {
            CancelView();
            CancelLayout();
            Type t = Type.GetType("campusMap.Models."+TYPE);
            Ijson_autocomplete theclass = (Ijson_autocomplete)Activator.CreateInstance(t);
            RenderText(theclass.get_json_data());
        }

and one off the models

namespace campusMap.Models
{
    [ActiveRecord(Lazy=true)]
    public class place_types : json_autocomplete<place_types>, campusMap.Models.Ijson_autocomplete
    {
        private int place_type_id;
        [PrimaryKey("place_type_id")]
        virtual public int id
        {
            get { return place_type_id; }
            set { place_type_id = value; }
        }

        private string Name;
        [Property]
        virtual public string name
        {
            get { return Name; }
            set { Name = value; }
        }

        private string Attr;
        [Property]
        virtual public string attr
        {
            get { return Attr; }
            set { Attr = value; }
        }
        private IList<place> places;
        [HasAndBelongsToMany(typeof(place), Lazy = true, Table = "place_to_place_models", ColumnKey = "place_model_id", ColumnRef = "place_id", Inverse = true, NotFoundBehaviour = NotFoundBehaviour.Ignore)]
        virtual public IList<place> Places
        {
            get { return places; }
            set { places = value; }
        }

    }
}

now when you call

/public/get_json.castle?wantedtype=place_types

or 

/public/get_json.castle?wantedtype=place_tags

You will get the json output of each model. Tada! :D Thank you everyone for helping.



来源：https://stackoverflow.com/questions/8332556/how-can-i-use-a-string-argument-to-case-a-namespace-or-type

标签
c#
.net
casting
castle-windsor
c#-2.0
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