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Free ASP.NET Hosting - HostForLIFE.eu :: How to Store Custom Objects in web.config

clock April 28, 2015 05:54 by author Rebecca

Normally, you used to have some data in appSettings section of web.config and read it when required. That is in string form, but there are lot more than this and you can update the data in web.config programmatically as well. You can store some object of custom type in web.config as well, which you normally don’t do it. But this can be very useful in several scenarios.

Have anyone tried to update some value or add some value in web.config? In this post, I'm going to tell you about web.config and how you can store the costum objects in web.config.

First, this is very common to have some constant data at appSettings section of web.config and read it whenever required. This is the way how to read data at appSettings:

//The data is stored in web.config as

<appSettings>

        <add key="WelcomeMessage" value="Hello All, Welcome to my Website." />

</appSettings>

// To read it
string message = ConfigurationManager.AppSettings["WelcomeMessage"];

If you want to update some data of appSettings programatically, you can do like this.

//Update header at config
        Configuration config = WebConfigurationManager.OpenWebConfiguration(Request.ApplicationPath);
        config.AppSettings.Settings["WelcomeMessage"].Value = "Hello All, Welcome to my updated site.";
        config.Save();


If you want to add some data in appSettings, you can add some app.config data as below:

//Update header at config
        Configuration config = WebConfigurationManager.OpenWebConfiguration(Request.ApplicationPath);
        config.AppSettings.Settings.Add("ErrorMessage", "An error has been occured during processing this request.");
        config.Save();


The above code is adding one new key value pair in web.config file. Now this can be read anywhere in the application.

Now, the question is, Can we store some custom data at config? The answer is YES! We can store some object. Let’s see how:

In this example, I have saved an object of my custom class NewError in web.config file. And also updating it whenever required.
To do this, Follow the below steps.

Step 1

Create a Class that inherit From ConfigurationSection (It is available under namespace System.Configuration ). Every property must have an attribute ConfigurationProperty, having attribute name and some more parameters. This name is directly mapped to web.config. Let’s see the NewError class:

public class NewError:ConfigurationSection
{
    [ConfigurationProperty ("Id",IsRequired = true)]
    public string ErrorId {
        get { return (string)this["Id"]; }
        set { this["Id"] = value; }
    }
    [ConfigurationProperty("Message", IsRequired = false)]
    public string Message {
        get { return (string)this["Message"]; }
        set { this["Message"] = value; }
    }
    [ConfigurationProperty("RedirectURL", IsRequired = false)]
    public string RedirectionPage
    {
        get { return (string)this["RedirectURL"]; }
        set { this["RedirectURL"] = value; }
    }
    [ConfigurationProperty("MailId", IsRequired = false)]
    public string EmailId
    {
        get { return (string)this["MailId"]; }
        set { this["MailId"] = value; }
    }
    [ConfigurationProperty("DateAdded", IsRequired = false)]
    public DateTime DateAdded
    {
        get { return (DateTime)this["DateAdded"]; }
        set { this["DateAdded"] = value; }
    }
}

You can see every property has attribute ConfigurationProperty with some value. As you can see the property ErrorId has attribute:

[ConfigurationProperty ("Id",IsRequired = true)]

it means ErrorId will be saved as Id in web.config file and it is required value. There are more elements in this attribute that you can set based on your requirement.
Now if you’ll see the property closely, it is bit different.

public string ErrorId {
get { return (string)this["Id"]; }
set { this["Id"] = value; }
}

Here the value is saved as the key “id”, that is mapped with web.config file.

Step 2

Now you are required to add/register a section in the section group to tell the web.config that you are going to have this kind of data. This must be in and will be as:

<section name="errorList"  type="NewError" allowLocation="true"

     allowDefinition="Everywhere"/>

Step 3

Now one can add that object in your config file directly as:

<errorList Id="1" Message="ErrorMessage" RedirectURL="www.google.com" MailId="[email protected]" ></errorList>

<errorList Id="1" Message="ErrorMessage" RedirectURL="www.google.com" MailId="[email protected]" ></errorList>

Step 4

And to read it at your page. Read it as follows:

NewError objNewError = (NewError)ConfigurationManager.GetSection("errorList");

And also a new object can be saved programmatically as

NewError objNewError = new NewError()
       {
         RedirectionPage="www.rediff.com",
         Message = "New Message",
         ErrorId="0",
         DateAdded= DateTime.Now.Date
       };
       Configuration config =
           WebConfigurationManager.OpenWebConfiguration(Request.ApplicationPath);

       config.Sections.Add("errorList", objNewError);
       config.Save();


Even one can add a custom group and have some custom elements in in this section. ASP.NET provides very powerfull APIs to read/edit the web.config file easily.

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Free ASP.NET Hosting - HostForLIFE.eu :: Calling ASP.NET Page Methods using AJAX

clock April 21, 2015 06:19 by author Rebecca

In this post, I tell you how to invoke an ASP.NET page method directly from your own AJAX library. A Page method is a method that is written directly in a page. It is generally called when the actual page is posted back and some event is raised from the client. The pageMethod is called directly from ASP.NET engine. To implement PageMethod, first you need to annotate our method as WebMethod. A WebMethod is a special method attribute that exposes a method directly as XML service.

Here are the steps to create the application:

Step 1

Start a new ASP.NET Project.

Step 2

Add JQuery to your page. Then, you can add a special JQuery plugin which stringify a JSON object. And post the codes like below :

(function ($) {
$.extend({
toJson: function (obj) {
var t = typeof (obj);
if (t != "object" || obj === null) {
// simple data type
if (t == "string") obj = '"' + obj + '"';
return String(obj);
}
else {
// recurse array or object
var n, v, json = [], arr = (obj && obj.constructor == Array);
for (n in obj) {
v = obj[n]; t = typeof (v);
if (t == "string") v = '"' + v + '"';
else if (t == "object" && v !== null) v = JSON.stringify(v);
json.push((arr ? "" : '"' + n + '":') + String(v));
}
return (arr ? "[" : "{") + String(json) + (arr ? "]" : "}");
}
}
});
// extend plugin scope
$.fn.extend({
toJson: $.toJson.construct
});
})(jQuery);

The code actually extends JQuery to add a method called toJSON to its prototype.

Step 3

Add the server side method to the Default.aspx page. For simplicity, you can actually return the message that is received from the client side with some formatting.

[WebMethod]
public static string DisplayTime(string message)
{
// Do something

return string.Format("Hello ! Your message : {0} at {1}", message, DateTime.Now.ToShortTimeString());
}


You should make this method static, and probably should return only serializable object.

Step 4

Add the following Html which actually puts one TextBox which takes a message and a Button to call server.

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
<h2>
Welcome to ASP.NET!
</h2>
<p>
Write Your message Here : <input type="text" id="txtMessage" />
</p>
<p>
<input type="button" onclick="javascript:callServer()" value="Call Server" />
</p>
</asp:Content>


Once you add this html to your default.aspx page, add some javascript to the page. We add the JQuery and our JSONStringify code to it.

<script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>
<script src="Scripts/JSONStringify.js" type="text/javascript"></script>

<script type="text/javascript">
function callServer() {
var objdata = {
"message" : $("#txtMessage").val()
};
$.ajax({
type: "POST",
url: "Default.aspx/DisplayTime",
data: $.toJson(objdata),
contentType: "application/json; charset=utf-8",
dataType: "json",
success: function (msg) {
alert(msg.d);
},
error: function (xhr, ajaxOptions) {
alert(xhr.status);
}
});
}
</script>


The above code actually invokes a normal AJAX call to the page. You can use your own library of AJAX rather than JQuery to do the same.

Hope it works for you!

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Free ASP.NET Hosting - HostForLIFE.eu :: How to Discover if Linked List contains Loops or Cycles in C# ?

clock April 17, 2015 07:11 by author Peter

In this post i will be able to show you how to discover loop in linked list with ASP.NET C#. We can notice the loop within the coupled list via Floyd’s Cycle-Finding formula, explained here. The method is pretty simple: We have a tendency to begin at the start of the linked list with 2 pointers. The primary pointer is incremented through every node of the list. The second pointer moves twice as quick, and skips each other node. If the coupled list contains a loop, these 2 pointers can eventually meet at the same node, so indicating that the linked list contains a loop.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks; 
namespace Algo
{
    public class Node
    {
        public Node Next { get; set; }
        public int Value { get; set; }
        public Node(int value)
        {
            this.Value = value;
        } 
    }
    public class LinkedList
    {        
    private Node _head;
        public LinkedList()
        { 
        }
        public void AppendLast(Node newNode)
        {
            if (_head == null)
            {
                _head = newNode;
            }
            else
            {
                Node current = _head;
                while (current.Next != null)
                {
                    current = current.Next;
                }
                current.Next = newNode;
            }
        }
        public override string ToString()
        {
            Node current = _head;
            StringBuilder builder = new StringBuilder();
            while (current != null)
            {
                builder.Append(current.Value + "->");
                current = current.Next;
            }
            return builder.ToString();
        }
        public bool IsCycle()
        {
            Node slow = _head;
            Node fast = _head;
            while (fast != null && fast.Next != null)
            {
                fast = fast.Next.Next;
                slow = slow.Next;
                if (slow == fast)
                    return true;
            }
            return false; 
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            LinkedList list = new LinkedList();
            list.AppendLast(new Node(10));
            list.AppendLast(new Node(20));
            list.AppendLast(new Node(30));
            Node cycle = new Node(40);
            list.AppendLast(cycle);
            list.AppendLast(new Node(60));
            list.AppendLast(cycle);
             if (list.IsCycle())
            {
                Console.WriteLine("Linked List is cyclic as it contains cycle or loop");
            }
            else
            {
                Console.WriteLine("LinkedList is not cyclic, no loop or cycle found");
            }   
        }
   }
}

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Free ASP.NET 5 Hosting - HostForLIFE.eu :: How to Create Profiles in ASP.NET

clock April 14, 2015 06:22 by author Rebecca

The ASP.NET Framework comes with the Profile object which an alternative to using cookies or session state to store user information. The Profile object provides you with a strongly typed, persistent form of session state.

You create a Profile by defining a list of Profile properties in your application root web configuration file. The ASP.NET Framework dynamically compiles a class that contains these properties in the background. The following web configuration file defines a Profile that contains three properties: firstName, lastName, and numberOfVisits.

File: Web.Config

<configuration>
<system.web>

  <profile>
    <properties>
      <add name="firstName" />
      <add name="lastName" />
      <add name="numberOfVisits" type="Int32" defaultValue="0" />
    <add name="xmlLastName" type="String" serializeAs="Xml"/>     
    </properties>
  </profile>

</system.web>
</configuration>

When you define a Profile property, you can use any of the following attributes:

  • name sets the name of the property.
  • type sets the type of the property.

The type can be any custom type, including a custom component that you define in the App_Code folder.

The default type is string.
defaultValue is a default value for the property.
readOnly creates a read-only property.

The default value is false.
serializeAs sets how a property is persisted into a static representation.
Possible values are Binary, ProviderSpecific, String, and Xml.

The default value is ProviderSpecific.
allowAnonymous allows anonymous users to read and set the property.

The default value is false.
provider associates the property with a particular Profile provider.
customProviderData passes custom data to a Profile provider.


File: ShowProfile.aspx

<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

    void Page_PreRender()
    {
        lblFirstname.Text = Profile.firstName;
        lblLastName.Text = Profile.lastName;

        Profile.numberOfVisits++;
        lblNumberOfVisits.Text = Profile.numberOfVisits.ToString();
    }
    protected void btnUpdate_Click(object sender, EventArgs e)
    {
        Profile.firstName = txtNewFirstName.Text;
        Profile.lastName = txtNewLastName.Text;
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show Profile</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    First Name:
    <asp:Label
        id="lblFirstname"
        Runat="server" />
    <br /><br />
    Last Name:
    <asp:Label
        id="lblLastName"
        Runat="server" />
    <br /><br />
    Number of Visits:
    <asp:Label
        id="lblNumberOfVisits"
        Runat="server" />

    <hr />

    <asp:Label
        id="lblNewFirstName"
        Text="New First Name:"
        AssociatedControlID="txtNewFirstName"
        Runat="server" />
    <asp:TextBox
        id="txtNewFirstName"
        Runat="server" />
    <br /><br />
    <asp:Label
        id="lblNewLastName"
        Text="New Last Name:"
        AssociatedControlID="txtNewLastName"
        Runat="server" />
    <asp:TextBox
        id="txtNewLastName"
        Runat="server" />
    <br /><br />
    <asp:Button
        id="btnUpdate"
        Text="Update Profile"
        OnClick="btnUpdate_Click"
        Runat="server" />

    </div>
    </form>
</body>
</html>

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FREE ASP.NET Hosting – HostForLIFE.eu :: Displaying SubTotal & Grand Total in ASP.NET 5

clock April 13, 2015 12:17 by author Peter

In this tutorial, I will show you how to Displaying SubTotal & Grand Total in ASP.NET 5. First, create new project. The records are isolated into Groups and after that SubTotal is calculated for every Group and then shown utilizing an element Row as a part of GridView. Now , I write the following code to create Products table:

CREATE TABLE [dbo].[Products](
     [ProductID] [int] NULL,
     [ProductName] [varchar](100) NULL,
     [CategoryID] [int] NULL,
     [UnitPrice] [decimal](18, 0) NULL,
     [QuantityPerUnit] [varchar](100) NULL
) ON [PRIMARY]
GO

First create new web apps and open your GridViewSubTotalTotal.aspx and write the following code:
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title> Displaying SubTotal & Grand Total in ASP.NET 5</title>
</head>
<body>
    <form id="form1" runat="server">
    <h3 style="color:Green">Display SubTotal and Grand Total in ASP.Net GridView</h3>
    <div>
        <asp:GridView ID="gvData" runat="server" BackColor="White" BorderColor="#CC9966"
            AutoGenerateColumns="false" BorderStyle="Solid" BorderWidth="1px" CellPadding="4"
            Font-Names="Tahoma" Font-Size="Small"  Width="475px" OnRowCreated="gvData_RowCreated"
nDataBound="gvData_OnDataBound">
            <Columns>
                <asp:BoundField DataField="ProductID" HeaderText="ProductID"  />
                <asp:BoundField DataField="CategoryID" HeaderText="Category ID" />
                <asp:BoundField DataField="ProductName" HeaderText="ProductName" />
                <asp:BoundField DataField="Price" HeaderText="Price"  DataFormatString="{0:N2}"/>
            </Columns>
            <FooterStyle BackColor="Tan" />
            <AlternatingRowStyle BackColor="#E6E6E1" />
            <FooterStyle BackColor="#FFFFCC" ForeColor="#330099" />
            <HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="#FFFFCC" />
        </asp:GridView>
    </div>
    </form>
</body>
</html>


Next step, write the code below:
GridViewSubTotalTotal.aspx.cs:
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Drawing;
public partial class GridViewSubTotalTotal : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
   {
        if (!IsPostBack)
        {
            BindGridData();
        }
    }
    protected void BindGridData()
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["ConString"].ConnectionString);
        string sqlQuery = "SELECT ProductID,ProductName,CategoryID,(UnitPrice*QuantityPerUnit) AS Price FROM Products";
        sqlQuery = sqlQuery + " WHERE CategoryID in(1,2,3) ORDER BY ProductID ASC";
        SqlCommand cmd = new SqlCommand(sqlQuery, con);
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        da.Fill(ds);
        gvData.DataSource = ds;
        gvData.DataBind();   
}
    int currentId = 0;
    decimal subTotal = 0;
    decimal total = 0;
    int subTotalRowIndex = 0;
    protected void gvData_RowCreated(object sender, GridViewRowEventArgs e)
    {
        subTotal = 0;
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            DataTable dt = (e.Row.DataItem as DataRowView).DataView.Table;
            int ProductID = Convert.ToInt32(dt.Rows[e.Row.RowIndex]["ProductID"]);
            total += Convert.ToDecimal(dt.Rows[e.Row.RowIndex]["Price"]);
            if (ProductID != currentId)
            {
                if (e.Row.RowIndex > 0)
                {
                    for (int i = subTotalRowIndex; i < e.Row.RowIndex; i++)
                    {
                        subTotal += Convert.ToDecimal(gvData.Rows[i].Cells[3].Text);
                    }
                    this.AddTotalRow("Sub Total", subTotal.ToString("N2"));
                    subTotalRowIndex = e.Row.RowIndex;
                }
                currentId = ProductID;
            }
        }
    }
    private void AddTotalRow(string labelText, string value)
    {
        GridViewRow row = new GridViewRow(0, 0, DataControlRowType.DataRow, DataControlRowState.Normal);
        row.BackColor = ColorTranslator.FromHtml("#FFA500");
        row.Cells.AddRange(new TableCell[4] {new TableCell { Text = labelText, HorizontalAlign = HorizontalAlign.Right},                                                          
 new TableCell (),
 new TableCell(), //Empty Cell,
 new TableCell { Text = value, HorizontalAlign = HorizontalAlign.Right }
);
        row.Cells[0].BorderColor = System.Drawing.Color.Orange;
        row.Cells[1].BorderColor = System.Drawing.Color.Orange;
        row.Cells[2].BorderColor = System.Drawing.Color.Orange;
        row.Cells[3].BorderColor = System.Drawing.Color.Orange;
        gvData.Controls[0].Controls.Add(row);
    }
    protected void gvData_OnDataBound(object sender, EventArgs e)
    {
        for (int i = subTotalRowIndex; i < gvData.Rows.Count; i++)
        {
            subTotal += Convert.ToDecimal(gvData.Rows[i].Cells[3].Text);
        }
        this.AddTotalRow("Sub Total", subTotal.ToString("N2"));
        this.AddTotalRow("Total", total.ToString("N2"));
    }
}


I hope this tutorial works for you!


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ASP.NET 5 Hosting - HostForLIFE.eu :: On Page Connection with ASP.NET 5

clock April 10, 2015 07:46 by author Peter

ASP.NET will gives you adaptability by they way you connect with databases. It would be ideal if you include the following code in your aspx page and check how to get connection on .aspx page. And here is the code that I used:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="onpageconnection.aspx.cs" Inherits="onpageconnection" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<%@ Import Namespace="System.Data.OleDb" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ import Namespace="System.Data" %>
<script  runat="server">
    protected void Page_Load(object sender, EventArgs e)
    {
        try
        {
            System.Data.SqlClient.SqlConnection con;
            sqlconn objconn = new sqlconn();
            con = objconn.getcon();
            con.Open();
            String str = "select * from EmpDemo";
            //SqlCommand cmd = new SqlCommand(str,con);
            //SqlDataReader adp;
            SqlDataAdapter adp = new SqlDataAdapter(str,con);
                        DataSet ds = new DataSet();
            adp.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();
            //Response.Write("connection open");       
}
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }
    }
</script>
<html>
<head>
<title></title>
</head>
<body>
<form id="Form1" runat="server">
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
</form>
</body>
</html>

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ASP.NET 5 Hosting - HostForLIFE.eu :: Configuring Your First Entity Framework in ASP.NET 5

clock April 7, 2015 12:33 by author Rebecca

If you're planning to get started with Entity Framework 7, at first you need to configuring the entity framework. The default is already there but when you need to update to the new versions, you must take a look at what is in the project.json file:

{
  /* Click to learn more about project.json  http://go.microsoft.com/fwlink/?LinkID=517074 */
  "webroot": "wwwroot",
  "version": "1.0.0-*",
  "dependencies": {
    "EntityFramework.SqlServer": "7.0.0-beta3",
    "EntityFramework.Commands": "7.0.0-beta3",
    "Microsoft.AspNet.Mvc": "6.0.0-beta3",

For your information, the startup.cs allowed for configuration to happen in two phases. First, the configuration of the different elements, then the registering of services with the dependency injection layer.

The service container is the dependency injection mechanism built into ASP.NET 5 and the ConfigureServices method is where that happens. Before you can add EF to the DI container, you need to get a connection string.

When I first came to ASP.NET 5, it looked as if the EF configuration would just load the connection string by convention, but it didn’t work. So I had to get it manually and add it (below) when I configured the context object.

// This method gets called by the runtime.
public void ConfigureServices(IServiceCollection services)
{
  var connectionString = Configuration.Get("Data:DefaultConnection:ConnectionString");

The Configuration.Get method allows it to read a setting from the list of configuration sources. Then, the Configuration object is a merge of the config.json file and any environment variables. In the case of the connection string, you’re looking for a string called “ConnectionString” inside an object graph. This should look obvious once you see the config.json file:

{
  "Data": {
    "DefaultConnection": {
      "ConnectionString": "Server=(localdb)\\MSSQLLocalDB;..."
    }
  },
  "EntityFramework": {
    "ApplicationDbContext": {
      "ConnectionStringKey": "Data:DefaultConnection:ConnectionString"
    }
  }
}

Now that we have the connection string, what's next?

You can add Entity Framework to the services collection by adding it this code below:

// Add EF services to the services container.
services.AddEntityFramework(Configuration)
    .AddSqlServer()
    .AddDbContext<MyCountriesContext>(options =>
    {
      options.UseSqlServer(connectionString);
    });

SUMMARY

The AddEntityFramework method adds EF to the dependency injection container so it can be served if needed later. Additionally, calling AddSqlServer specifies the data store you’ll be using. Finally, the AddDbContext adds a DbContext object to the EF service. The options lambda allows us to specify the connection string. I suspect this extra step will go away at some point and just read from the configuration by convention, but at this point it’s necessary. If we need the context in another part of the system (e.g. Controllers) we can just let ASP.NET 5 serve it to us in the constructor like any other dependency injection framework.

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ASP.NET 5 Hosting - HostForLIFE.eu :: How to Use POCO Controllers in ASP.NET 5

clock April 2, 2015 13:21 by author Rebecca

As you know, ASP.NET 5 supports POCO controllers. The controller classes doesn’t extend Controller base class. These controllers look a little bit different by some small aspects and sometime,s you may need to help framework detect our POCO controllers. In this post, I will give you complete overview of POCO controllers in ASP.NET 5.

Creating POCO controllers is simple. To use views and other goodies provided by controllers base class we have to use dependency injection to get required services to our POCO controller. If we don’t use MVC regular naming style for controllers we have to write action discovery convention and register it with built-in dependency injection service. To provide common strategy to detect POCO controllers with arbitrary names we can use special attribute or interface for this. We still can inherit our POCO controllers from classes we want. Here is the simple steps that you have to follow:

Simple POCO Controllers

First let’s define that simple controller doesn’t inherit from Controller base class. Follow the code below:

public class PocoController
{
    public IActionResult Index()
    {
        return new ContentResult() { Content = “Hello from POCO controller!” };
    }
}

And to make this controller work with views, you need some additional code.

public class PocoController
{
    private readonly IModelMetadataProvider _metadataProvider;
 
    public PocoController(IModelMetadataProvider metadataProvider)
    {
        _metadataProvider = metadataProvider;
    }
 
    public IActionResult Index()
    {
        var viewData = new ViewDataDictionary<string>(_metadataProvider);
        viewData.Model = “Hello from POCO controller!”;
 
        return new ViewResult() { ViewData = viewData };
    }
}

Now, you have basic primitive POCO controller that you can use in ASP.NET 5.

The second thing that you have to is use a small trick and call our controller just as "POCO" using this code:

public class Poco
{
    // …
}

When trying to use controller now you have run to problems like this. Why? Because ASP.NET cannot detect controller anymore.

How to make the controller is detected by default?

When sniffing around in MVC source you can find the method that MVC uses to find out if given type is controller type of not. It is done in DefaultActionDiscoveryConventions class.

public virtual bool IsController([NotNull] TypeInfo typeInfo)
{
    if (!typeInfo.IsClass ||
        typeInfo.IsAbstract ||
        typeInfo.ContainsGenericParameters)
    {
        return false;
    }
 
    if (typeInfo.Name.Equals(“Controller”, StringComparison.OrdinalIgnoreCase))
    {
        return false;
    }

    return typeInfo.Name.EndsWith(“Controller”, StringComparison.OrdinalIgnoreCase) ||
           typeof(Controller).GetTypeInfo().IsAssignableFrom(typeInfo);

If we have POCO controller andyou don’t name it as SomethingController then MVC is not considering our POCO controller as controller.

Using action discovery convention

If there are additional rules for detecting controllers, you can use action discovery conventions to tell MVC if class is constructor or not. Here is simple discovery convention class that works with our POCO controller.

public class MyActionDiscoveryConventions : DefaultActionDiscoveryConventions
{
    public override bool IsController(TypeInfo typeInfo)
    {
        var isController = base.IsController(typeInfo);
        return isController || typeInfo.Name.Equals(“Poco”, StringComparison.OrdinalIgnoreCase);
    }
}


To make MVC use this class, you have to register it with built-in dependency injection system. You will do it in ConfigureServices() method of your Startup class by calling AddTransient() method.

public void ConfigureServices(IServiceCollection services)
{
    // …
    services.AddMvc();
 
    services.AddTransient<IActionDiscoveryConventions, MyActionDiscoveryConventions>();

}

If you run your application now and try to use POCO controller it works again.

Defining ControllerAttribute

If you are building some extensible system and you need some better way how to detect controllers then besides naming controllers appropriately you can also define attribute in some API library that is available for developers.

public class ControllerAttribute : Attribute
{
}
Other developers who are building plugins for your system can decorate their controllers with this attribute.

[Controller]
public class Poco
{
    // …
}

And here is how you can detect controller in action discovery convention.

public class MyActionDiscoveryConventions : DefaultActionDiscoveryConventions
{
    public override bool IsController(TypeInfo typeInfo)
    {
        var isController = base.IsController(typeInfo);
        return isController || HasControllerAttribute(typeInfo);
    }
 
    private bool HasControllerAttribute(TypeInfo typeInfo)
    {
        return typeInfo.GetCustomAttribute<ControllerAttribute>(true) != null;
    }
}

You can also use marker interface for POCO controllers or some interface with properties and methods defined if your POCO controllers have to provide some functionalities.

HostForLIFE.eu ASP.NET 5 Hosting
HostForLIFE.eu is European Windows Hosting Provider which focuses on Windows Platform only. We deliver on-demand hosting solutions including Shared hosting, Reseller Hosting, Cloud Hosting, Dedicated Servers, and IT as a Service for companies of all sizes. We have customers from around the globe, spread across every continent. We serve the hosting needs of the business and professional, government and nonprofit, entertainment and personal use market segments.



About HostForLIFE.eu

HostForLIFE.eu is European Windows Hosting Provider which focuses on Windows Platform only. We deliver on-demand hosting solutions including Shared hosting, Reseller Hosting, Cloud Hosting, Dedicated Servers, and IT as a Service for companies of all sizes.

We have offered the latest Windows 2012 Hosting, ASP.NET 4.5 Hosting, ASP.NET MVC 4 Hosting, ASP.NET MVC 5 Hosting and SQL 2014 Hosting.


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