Once you finish developing an ASP.NET Core web application, you need to deploy it on a server so that end users can start using it. When it comes to deployment to IIS, ASP.NET Core offers two hosting models namely InProcess and OutOfProcess. In this article you learn about these hosting models and how to configure them.

When you deploy your web application to IIS, various requests to the application are handled by what is known as ASP.NET Core Module. Under default settings the hosting model for your application is InProcess. This means ASP.NET Core Module forwards the requests to IIS HTTP Server (IISHttpServer). The IIS HTTP Server is a server that runs in-process with IIS. This results in great performance as compared to Out Of Process model. In-process models bypasses built-in Kestrel web server of ASP.NET Core.

If you decide to use Out-Of-Process hosting model then IIS HTTP Server won't be used. Instead Kestrel web server is used to process your requests. So, ASP.NET Core Module forwards your requests to Kestrel web server. This communication is out-of-process communication and is therefore slower than the in-process model.

Now that you have some basic idea about the in-process and out-of-process hosting models let's see how to configure them.

In order to understand the hosting models discussed in this article you first need to create an ASP.NET Core web application using Visual Studio. So, go ahead and do so based on any of the web application project templates. Make sure to use ASP.NET Core version 2.2 or later.

Once you create the project, click on the Build > Publish menu and Web Deploy the output (or manually copy to IIS) to IIS. Once you finish deploying the application locate the web.config file generated during the deployment process. In this web.config you will find a section like this:

<system.webServer>
  <handlers>
    <add name="aspNetCore" path="*" verb="*"
modules="AspNetCoreModuleV2" />
  </handlers>
  <aspNetCore processPath="dotnet"
              arguments=".\MyWebApp.dll"  
              stdoutLogEnabled="false"
              stdoutLogFile=".\logs\stdout"
              hostingModel="inprocess" />
</system.webServer>

As you can see the <aspNetCore> tag has hostingModel attribute that is set to inprocess by default.

Now, run the application from the browser with this default setting in place and observe the HTTP headers. The following figure shows one such sample run of the application.

As you can see the Server is Microsoft IIS.

Now, change the hostingModel attribute from inprocess to outofprocess. Run the application again. This time you will get the following output:

As you can see the Server is now Kestrel indicating that Out-Of-Process model is active.

In the preceding example you change the hosting model in the web.config generated during the publish operation. You can also specify the hosting model in project's .csproj file. Consider the following markup from .csproj file that does that.

<PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
    <AspNetCoreHostingModel>InProcess</AspNetCoreHostingModel>
</PropertyGroup>

The <AspNetCoreHostingModel> element sets the hosting model to InProcess. To set it to Out-Of-Process you need to set it like this:

<AspNetCoreHostingModel>OutOfProcess</AspNetCoreHostingModel>

Run the application with these settings and confirm whether you get the outcome as before.

That's it for now! Keep coding!!

In this version, I will tell you about using Let us see how to use Distinct() and FirstOrDefault() clauses with the help of linq.js in .NET Web Application. It's useful to write simple LINQ queries from Entityframework to client side with LinqJS.

It’s better for validating data at the client side.
Improves performance of the application.

Let’s see one by one,
Distinct() function is different here.

C#.NET Code
    var FirstNameCollection = myDataArray.Select(x => x.FirstName).Distinct(); 
LinqJS Code
    // Retrieves non-duplicate FirstName values. 
    var FirstNameCollection = Enumerable.From(myDataArray).Distinct(function(x) { 
        return x.FirstName; 
    }).Select(function(FName) { 
        return FName; 
    }).ToArray(); 
The FirstOrDefault() function is nearly similar.

C#.NET Code
    public class cmbMonthOfWeek { 
        public string cmbMonth { 
            get; 
            set; 
        } 
        public int Id { 
            get; 
            set; 
        } 
    } 
    List < cmbMonthOfWeek > weekInfo = new List < cmbMonthOfWeek > (); 
    weekInfo.Add(new cmbMonthOfWeek { 
        cmbMonth = "First week", Id = 0 
    }); 
    weekInfo.Add(new cmbMonthOfWeek { 
        cmbMonth = "Second week", Id = 1 
    }); 
    weekInfo.Add(new cmbMonthOfWeek { 
        cmbMonth = "Third week", Id = 2 
    }); 
    weekInfo.Add(new cmbMonthOfWeek { 
        cmbMonth = "Fourth week", Id = 3 
    }); 
    var defaultWeekData = (from p in weekInfo where p.Id == 1 select p).FirstOrDefault();
Note

Here in defaultWeekData, you will get cmbMonth = "Second week".

LinqJS Code
    $scope.cmbMonthOfWeek = [{ 
        "cmbMonth": "First week", 
        "Id": 0 
    }, { 
        "cmbMonth": "Second week", 
        "Id": 1 
    }, { 
        "cmbMonth": "Third week", 
        "Id": 2 
    }, { 
        "cmbMonth": "Fourth week", 
        "Id": 3 
    }, ]; 
    var defaultWeekData = Enumerable.From($scope.cmbMonthOfWeek).Where(function(x) { 
        return x.Id == 1 
    }).FirstOrDefault();  Distinct And FirstOrDefault Clauses In .NET Using linq.js

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Rather than writing try catch block for each method, throwing exceptions manually and handling them, here we will use the power of .Net Core middleware to handle the exceptions at one single place, so that when an exception occurs anywhere in the code, the appropriate action can be taken. We will use UseExceptionHandler extension method that will add a middleware to the pipeline, and it will catch exceptions, log them, reset the request path, and re-execute the request if response has not already started.

Developer can customize the response format as well.

To achive this in .NetCore 2.2, this code snippet is very simple and it's just a matter of adding a few lines in your Startup.cs.

Simply go in Configure method and add the below code,
if (env.IsDevelopment()) {  
    app.UseDeveloperExceptionPage();  
} else {  
    app.UseExceptionHandler(errorApp => errorApp.Run(async context => {  
        // use Exception handler path feature to catch the exception details   
        var exceptionHandlerPathFeature = context.Features.Get < IExceptionHandlerPathFeature > ();  
        // log errors using above exceptionHandlerPathFeature object   
        Console.WriteLine(exceptionHandlerPathFeature ? .Error);  
        // Write a custom response message to API Users   
        context.Response.StatusCode = "500";  
        // Set a response format    
        context.Response.ContentType = "application/json";  
        await context.Response.WriteAsync("Some error occured.");  
    }));  
}  

The Console.WriteLine() is for demonstration purposes only. Here a developer can log the exceptions using any tool/package getting used in their project.

When any exceptions are thrown in the application this code will be executed and will produce the desired custom response in non-development environments (as in a development env we are using UseDeveloperExceptionPage() as a middleware).

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In this post, I will tell you about fix System.Web.UI.ViewStateException: Invalid viewstate or System.Web.HttpException: The client disconnected exception Response.IsClientConnected Property ASP.NET 4.8.What is HttpResponse.IsClientConnected Property: HttpResponse.IsClientConnected used to gets a quality demonstrating whether the customer is still joined with the server.

The accompanying illustration utilizes the IsClientConnected property to check whether the customer that is asking for the page remains connected to the server. IfIsClientConnected is genuine, the code calls the  Redirect  technique, and the client will see an alternate page. In the event that IsClientConnected is false, then the code calls the End system and all page handling is ended.

And here is code that I used:
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Fix System.Web.UI.ViewStateException
    </title></head>
<body>
    <form id="form1" runat="server">
    <div>Welcome</div>
    </form>
</body>
</html>

C#
public partial class ClientDisconnected : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        //Check whether the browser(client) remains connected to the server
        if (Response.IsClientConnected)
        {
            // if  browser connected, redirect to the Main.aspx page
            Response.Redirect("~/Main.aspx");
        }
        else
        {
            //if browser is not connected,terminate all response processing.
            Response.End();
        }
    }
}

VB.NET
Public Partial Class ClientDisconnected
    Inherits System.Web.UI.Page
    Protected Sub Page_Load(sender As Object, e As EventArgs)
        'Check whether the browser(client) remains connected to the server
        If Response.IsClientConnected Then
            ' if  browser connected, redirect to the Main.aspx page
            Response.Redirect("~/Main.aspx")
        Else
            'if browser is not connected,terminate all response processing.
            Response.[End]()
        End If
    End Sub
End Class

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This article explains the concept of the AdRotator control without the user refreshing the page and rotates the ads on a certain time interval. This article also gives a tip to fetch ad information from an XML file. The AdRotator Control presents ad images each time a user enters or refreshes a webpage. When the ads are clicked, it will navigate to a new web location. However the ads are rotated only when the user refreshes the page. In this article, we will explore how you can easily rotate ads at regular intervals, without the user refreshing the page. First of all start Visual Studio .NET And make a new ASP.NET web site using Visual Studio 2010.
 
Now you have to create a web site.
Go to Visual Studio 2010
New-> Select a website application
Click OK

Now add a new page to the website.

    Go to the Solution Explorer
    Right-click on the Project name
    Select add new item
    Add new web page and give it a name
    Click OK

We create an images folder in the application which contains some images to rotate in the AdRotator control. Now add a XML file. To do so, right-click the App_Data folder > Add New Item > 'XML File' > Rename it to adXMLFile.xml and click Add. Put this code in the .XML File.

    <?xml version="1.0" encoding="utf-8" ?> 
    <Advertisements> 
    <Ad> 
    <ImageUrl>~/Images/image1.gif</ImageUrl> 
    <NavigateUrl>http://www.c-sharpcorner.com/</NavigateUrl> 
    <AlternateText>C-sharpcorner Home Page</AlternateText> 
    <Impressions>3</Impressions> 
    <Keyword>small</Keyword> 
    </Ad> 
    <Ad> 
    <ImageUrl>~/images/forest_wood.JPG</ImageUrl> 
    <NavigateUrl>http://www.c-sharpcorner.com/</NavigateUrl> 
    <AlternateText>C-sharpcorner Home Page</AlternateText> 
    <Impressions>2</Impressions> 
    <Keyword>small</Keyword> 
    </Ad> 
    <Ad> 
    <ImageUrl>~/images/image2.gif</ImageUrl> 
    <Width>300</Width> 
    <Height>50</Height> 
    <NavigateUrl>http://www.c-sharpcorner.com/</NavigateUrl> 
    <AlternateText>C-sharpcorner Home Page</AlternateText> 
    <Impressions>3</Impressions> 
    <Keyword>small</Keyword> 
    </Ad> 
    </Advertisements> 

XML file elements

• Here is a list and a description of the <Ad> tag items.
• ImageUrl - The URL of the image to display.
• NavigateUrl - The URL where the page will go after AdRotator image is clicked.
• AlternateText - Text to display if the image is unavailable.
• Keyword - Category of the ad, which can be used to filter for specific ads.
• Impressions - Frequency of ad to be displayed. This number is used when you want some ads to be displayed more frequently than others.
• Height - Height of the ad in pixels.
• Width - Width of the ad in pixel.

Now drag and drop an AdRotator control from the toolbox to the .aspx and bind it to the advertisement file. To bind the AdRotator to our XML file, we will make use of the "AdvertisementFile" property of the AdRotator control as shown below:
    <asp:AdRotator 
    id="AdRotator1" 
    AdvertisementFile="~/adXMLFile.xml" 
    KeywordFilter="small" 
    Runat="server" /> 

To rotate the ads without refreshing the page, we will add some AJAX code to the page.
    <Triggers> 
    <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" /> 
    </Triggers> 

The .aspx code will be as shown below.
 
Now drag and drop an UpdatePanel and add an AdRotator control into it. The DataList code looks like this:
    <%@ Page Language="C#" AutoEventWireup="true" CodeFile="adrotator.aspx.cs" Inherits="adrotator" %> 
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
    <html xmlns="http://www.w3.org/1999/xhtml"> 
    <head runat="server"> 
    <title></title> 
    </head> 
    <body> 
    <form id="form1" runat="server"> 
    <div> 
    <asp:ScriptManager ID="ScriptManager1" runat="server" /> 
    <asp:Timer ID="Timer1" Interval="1000" runat="server" /> 
    <asp:UpdatePanel ID="up1" runat="server"> 
    <Triggers> 
    <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" /> 
    </Triggers> 
    <ContentTemplate> 
    <asp:AdRotator ID="AdRotator1" AdvertisementFile="~/adXMLFile.xml" KeywordFilter="small" 
    runat="server" /> 
    </ContentTemplate> 
    </asp:UpdatePanel> 
    </div> 
    </form> 
    </body> 
    </html> 

Now run the application and test it. The AdRotator control rotates the ads without the user refreshing the page and rotates the ads on a certain time interval

In this article, we will learn to access the Session data in a Typed manner by getting IntelliSense support. We learned how to use Session in ASP.NET Core. In this article, we'll learn about Session Wrapper design pattern to ease the access of Session. In short, we'll make our access of session "Typed". Also, we may apply any validation or constraint in this wrapper class.

Step 1 - Create a Session Manager class
In this example, we are going to store two items in Session (i.e. ID & LoginName).
We are injecting IHttpContextAccessor so that we can access the Session variable.
We are creating properties which are actually accessing Session variable and returning the data or writing the data to Session.
We have added one helping property "IsLoggedIn" which is using other properties to make a decision. We may have more such helping/wrapper properties.
using Microsoft.AspNetCore.Http;

public class SessionManager 
{ 
    private readonly ISession _session; 
    private const String ID_KEY = "_ID"; 
    private const String LOGIN_KEY = "_LoginName"; 
    public SessionManager(IHttpContextAccessor httpContextAccessor) 
    { 
        _session = httpContextAccessor.HttpContext.Session; 
    } 

    public int ID 
    { 
        get 
        { 
            var v = _session.GetInt32(ID_KEY); 
            if (v.HasValue) 
                return v.Value; 
            else 
                return 0; 
        } 
        set 
        { 
            _session.SetInt32(ID_KEY, value); 
        } 
    } 
    public String LoginName 
    { 
        get 
        { 
            return _session.GetString(LOGIN_KEY); 
        } 
        set 
        { 
            _session.SetString(LOGIN_KEY, value); 
        } 
    } 
    public Boolean IsLoggedIn 
    { 
        get 
        { 
            if (ID > 0) 
                return true; 
            else 
                return false; 
        } 
    } 
} 

Step 2
Registering IHttpContextAccessor and SessionManager in Startup file.
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>(); 
services.AddScoped<SessionManager>(); 

Step 3
Injecting SessionManager in your classes. Here is an example of Controller class but in the same way, it can be injected in non-controller classes too.
private readonly SessionManager _sessionManager; 
public HomeController(SessionManager sessionManager) 
{ 
  _sessionManager = sessionManager; 
} 

Step 4
Using SessionManager to access Session Data,
_sessionManager.ID = 1; 
_sessionManager.LoginName = dto.Login; 

if(_sessionManager.IsLoggedIn == true) 
{ 
ViewBag.Login = _sessionManager.LoginName; 
return View(); 
} 

Conclusion
This wrapper pattern helps using Session without worrying about KeyNames & Makes access easier. It also helps you apply different conditioning and constraints in a wrapper class.

Today, I will discuss about Serilog. What is Serilog? Serilog is an open source event library for .NET. Serilog gives you two important components: loggers and sinks (outputs). Most applications will have a single static logger and several sinks, so in this example I’ll use two: the console and a rolling file sink.

Starting with a new ASP.NET Core 2.0 Web Application running on .NET Framework (as in the image to the right), begin by grabbing a few packages off NuGet:

• Serilog
• Serilog.AspNetCore
• Serilog.Settings.Configuration
• Serilog.Sinks.Console
• Serilog.Sinks.RollingFile

Next, you will need to modify some files.

Startup.cs

Startup constructor

Create the static Log.Logger by reading from the configuration (see appsettings.json below). The constructor should now look like this:

public Startup(IConfiguration configuration)
{
   Log.Logger = new LoggerConfiguration().ReadFrom.Configuration(configuration).CreateLogger();
Configuration = configuration;
}

BuildWebHost method

Next, add the .UseSerilog() extension to the BuildWebHost method. It should now look like this:

public static IWebHost BuildWebHost(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.UseStartup<Startup>()
.UseSerilog() // <-- Add this line
.Build();

The BuildWebHost method might look strange because the body of this method is called an expression body rather than a traditional method with a statement body.

Configure method

At the start of the configure method, add one line at the top to enable the Serilog middleware. You can optionally remove the other loggers as this point as well. Your Configure method should start like this:

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
     loggerFactory.AddSerilog(); // <-- Add this line
     ...

appsettings.json

At the root level of the appsettings.json (or one of the environment-specific settings files), add something like this:

"Serilog": {
     "Using": [ "Serilog.Sinks.Console" ],
     "MinimumLevel": "Debug",
     "WriteTo": [
            { "Name": "Console" },
            {
                    "Name": "RollingFile",
                    "Args": {
                          "pathFormat": "logs\\log-{Date}.txt",
                          "outputTemplate": "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level}] {Message}{NewLine}{Exception}"
                    }
            }
     ],
     "Enrich": [ "FromLogContext", "WithMachineName", "WithThreadId" ],
     "Properties": {
     "Application": "My Application"
            }
}

If you’re wondering about the pathFormat and what other parameters you can use, there aren’t that many. {Date} is the only “switch” you can use with this particular sink. But you can use any environment variable (things like %TEMP%), allowing for a pathFormat of:

"%TEMP%\\logs\\log-{Date}.txt"

The outputTemplate has a LOT of options that I won’t get into here because the official documentation does a great job of explaining it.

As for the event levels, I’ve copied the list below from the official documentation for reference.

1. Verbose – tracing information and debugging minutiae; generally only switched on in unusual situations
2. Debug – internal control flow and diagnostic state dumps to facilitate pinpointing of recognised problems
3. Information – events of interest or that have relevance to outside observers; the default enabled minimum logging level
4. Warning – indicators of possible issues or service/functionality degradation
5. Error – indicating a failure within the application or connected system
6. Fatal – critical errors causing complete failure of the application

You’ll also notice in the above JSON that the “Using” property is set to an array containing “Serilog.Sinks.Console” but not “Serilog.Sinks.RollingFile”. Everything appears to work, so I am not sure what impact this property has.  

My work is to create an excel file, which will contain 3 fields: Address, Latitude and longitude.The user will upload an Address in an excel file and after reading the addresses from an excel file, I have to retrieve Latitude and longitude, using Bing MAP API and build another excel file, which can contain Addresses beside the Latitude and longitude of that address and download the new excel file to the user's end.

Create a MVC Application and add EPPLUS from NuGet package manager to your solution.

Now, Add the code to your .cshtml page.

<h2>Upload File</h2> 
 
sing (Html.BeginForm("Upload", "Home", null, FormMethod.Post, new { enctype = "multipart/form-data" })) 
  { 
      @Html.AntiForgeryToken() 
      @Html.ValidationSummary() 
 
      <div class="form-group"> 
          <input type="file" id="dataFile" name="upload" /> 
      </div> 
 
      <div class="form-group"> 
          <input type="submit" value="Upload" class="btn btn-default" /> 
      </div> 
 
       
  } 

And then, add the code, mentioned below to your controller.

[HttpPost] 
        public ActionResult Upload(HttpPostedFileBase upload) 
        { 
            if (ModelState.IsValid) 
            { 
                if (Path.GetExtension(upload.FileName) == ".xlsx") 
                { 
                    ExcelPackage package = new ExcelPackage(upload.InputStream); 
            //From This part we will read excel file 
                    DataTable dt = ExcelPackageExtensions.ToDataTable(package); 
 
 
                    DataTable dtExcel = new DataTable(); 
                    dtExcel.Columns.Add("Address", typeof(String)); 
                    dtExcel.Columns.Add("LAT", typeof(Double)); 
                    dtExcel.Columns.Add("LONG", typeof(Double)); 
 
                    List<Coordinates> lstCor = new List<Coordinates>(); 
                    for (int i = 0; i < dt.Rows.Count; i++) 
                    { 
                        //Fill the new data Table to generate new excel file 
                    } 
            //This method will generate new excel and download the same 
                    generateExcel(dtExcel);                  
                } 
            } 
            return View(); 
        } 

“ExcelPackageExtensions.ToDataTable(package)” for this create a new class with the name ExcelPackageExtensions and create a static method with the name “ToDataTable()”. The code is mentioned below.

public static class ExcelPackageExtensions 
    { 
        public static DataTable ToDataTable(this ExcelPackage package) 
        { 
            ExcelWorksheet workSheet = package.Workbook.Worksheets.First(); 
            DataTable table = new DataTable(); 
            foreach (var firstRowCell in workSheet.Cells[1, 1, 1, workSheet.Dimension.End.Column]) 
            { 
                table.Columns.Add(firstRowCell.Text); 
            } 
 
            for (var rowNumber = 2; rowNumber <= workSheet.Dimension.End.Row; rowNumber++) 
            { 
                var row = workSheet.Cells[rowNumber, 1, rowNumber, workSheet.Dimension.End.Column]; 
                var newRow = table.NewRow(); 
                foreach (var cell in row) 
                { 
                    newRow[cell.Start.Column - 1] = cell.Text; 
                } 
                table.Rows.Add(newRow); 
            } 
            return table; 
        } 
    } 

Now, add the code part to generate and download an Excel file.
[NonAction] 
        public void generateExcel(DataTable Dtvalue) 
        { 
            string excelpath = ""; 
            excelpath = @"C:\Excels\abc.xlsx";//Server.MapPath("~/UploadExcel/" + DateTime.UtcNow.Date.ToString() + ".xlsx"); 
            FileInfo finame = new FileInfo(excelpath); 
            if (System.IO.File.Exists(excelpath)) 
            { 
                System.IO.File.Delete(excelpath); 
            } 
            if (!System.IO.File.Exists(excelpath)) 
            { 
                ExcelPackage excel = new ExcelPackage(finame); 
                var sheetcreate = excel.Workbook.Worksheets.Add(DateTime.UtcNow.Date.ToString()); 
                if (Dtvalue.Rows.Count > 0) 
                { 
                    for (int i = 0; i < Dtvalue.Rows.Count; ) 
                    { 
                        sheetcreate.Cells[i + 1, 1].Value = Dtvalue.Rows[i][0].ToString(); 
                        sheetcreate.Cells[i + 1, 2].Value = Dtvalue.Rows[i][1].ToString(); 
                        sheetcreate.Cells[i + 1, 3].Value = Dtvalue.Rows[i][2].ToString(); 
                        i++; 
                    } 
                } 
                //sheetcreate.Cells[1, 1, 1, 25].Style.Font.Bold = true; 
                //excel.Save(); 
 
                var workSheet = excel.Workbook.Worksheets.Add("Sheet1"); 
                //workSheet.Cells[1, 1].LoadFromCollection(data, true); 
                using (var memoryStream = new MemoryStream()) 
                { 
                    Response.ContentType = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"; 
                    Response.AddHeader("content-disposition", "attachment;  filename=Contact.xlsx"); 
                    excel.SaveAs(memoryStream); 
                    memoryStream.WriteTo(Response.OutputStream); 
                    Response.Flush(); 
                    Response.End(); 
                } 
            } 
 
        } 

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This code will help the developers to check and uncheck the gridview checkbox based on the value from the database.
Create a GridView with checkbox.

<asp:GridView ID="Gridview" runat="server" Font-Size="8pt" 
        PageSize="200" Width="880px" AutoGenerateColumns="False"> 
        <Columns> 
            <asp:TemplateField> 
                <HeaderTemplate> 
                    <asp:CheckBox ID="chkHeader" Text="Select All" runat="server" /> 
                </HeaderTemplate> 
                <ItemTemplate> 
                    <asp:CheckBox ID="chkChild" runat="server"  Checked='<%# Eval("PROCESSED").ToString().Equals("1") %>' Enabled='<%# !Eval("PROCESSED").ToString().Equals("1") %>'/> 
                </ItemTemplate> 
            </asp:TemplateField>            
        </Columns> 
    </asp:GridView> 

Get the data from the database, the field from the database to check the checkbox should be 1 or 0.

DB Table data

PROCESSED (HEADER)
1
1
0

DataField "PROCESSED" should be 1 or 0 (boolean),

Checked='<%# Eval("PROCESSED").ToString().Equals("1") %>' 

The above GridView code will check the checkbox if the value from the PROCESSED field in DB is 1 else if the PROCESSED value is other than 1 the checkbox will be unchecked,

Enabled='<%# !Eval("PROCESSED").ToString().Equals("1") %>' 

This code will help us to enable or disable the text box. In the above mentioned code, if the PROCESSED is 1, checkbox will be disabled else the checkboc will be enable.

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PROGRAMMING LANGUAGE SUPPORT
From a programming point of view C#, Visual Basic, and F# languages can be used to write applications and libraries for .NET Core. Additionally, with .NET Core 3.0 C# 8.0 will be supported. Currently, VB.NET compiles and runs on .NET Core, but the separate Visual Basic Runtime is not implemented. Microsoft announced that .NET Core 3 would include the Visual Basic Runtime.

Use .NET Core when

• You want to build cross-platform applications
• If the new application (web or service) needs to run on multiple platforms- Windows, Linux, macOS, choose .NET Core over .NET Framework. Visual Studio Code and third-party editors such as Sublime, Emacs, VI support .NET Core for cross-platform development.
• The need is to build high-performance and scalable systems
• When a performance-oriented and scalable system is on the list, it is better to prefer .NET Core over the .NET Framework. Reason being, .NET Core offers high-performance server runtime for Linux and Windows Server.
• When you are using microservices or Docker containers
• For applications or services that use microservices or Docker containers, opting .NET Core makes more sense. Reasons include,
  
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• You need side-by-side .NET versions per application
• For applications that may have a dependency on different versions of .NET for installation, opt for .NET Core. .NET Core offers side by side installation of multiple versions for .NET Core runtime on the same machine.

Use the .NET Framework when:

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• The existing app uses a platform that .NET Core does not support.
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