July 27, 2023 09:50 by
PeterIn .NET Core, there are problems such as the bad complexity of web programming and the vagueness of coding in the controller, and the destruction of the web programming structure on the server side. Also, one of the negative points of .NET Core is the lack of support for aspx files. An executable physical file (aspx) in the root makes your program more structured.
Introducing Code-Behind
This style is completely based on MVC, and in the near future, we will expand it in such a way that there is no need for coding the view part, such as for, foreach, and while loops.
Write code with Code-Behind
You can add aspx files in the wwwroot directory and its subdirectories.
An example of an aspx file based on Code-Behind.
<%@ Page Controller="YourProjectName.wwwroot.DefaultController" Model="YourProjectName.wwwroot.DefaultModel" %><!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title><%=model.PageTitle%></title>
</head>
<body>
<%=model.BodyValue%>
</body>
</html>
An example of a controller class that is based on Code-Behind.
using CodeBehind;
namespace YourProjectName.wwwroot
{
public partial class DefaultController : CodeBehindController
{
public DefaultModel model = new DefaultModel();
public void PageLoad(HttpContext context)
{
model.PageTitle = "My Title";
model.BodyValue = "HTML Body";
View(model);
}
}
}
An example of a model class that is based on Code-Behind.
using CodeBehind;
namespace YourProjectName.wwwroot
{
public partial class DefaultModel : CodeBehindModel
{
public string PageTitle { get; set; }
public string BodyValue { get; set; }
}
}
Program file and additional Code-Behind items.
using CodeBehind;
using SetCodeBehind;
var builder = WebApplication.CreateBuilder(args);
var app = builder.Build();
// Configure the HTTP request pipeline.
if (!app.Environment.IsDevelopment())
{
app.UseExceptionHandler("/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
app.UseHsts();
}
+ CodeBehindCompiler.Initialization();
app.Run(async context =>
{
+ CodeBehindExecute execute = new CodeBehindExecute();
+ await context.Response.WriteAsync(execute.Run(context));
});
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.Run();
In the Program.cs class codes above, the three values marked with the + character must be added.
We show the codes separately for you.
CodeBehindCompiler.Initialization();
CodeBehindExecute execute = new CodeBehindExecute();
await context.Response.WriteAsync(execute.Run(context));
You can use the Write method in the model and controller classes; the Write method adds a string value to the ResponseText attribute; you can also change the values of the ResponseText attribute by accessing them directly.
In the controller class, there is an attribute named IgnoreViewAndModel attribute, and if you activate the IgnoreViewAndModel attribute, it will ignore the values of model and view, and you will only see a blank page; this feature allows you to display the values you need to the user and avoid multiple redirects and transfers.
To receive the information sent through the form, you can follow the instructions below.
public DefaultModel model = new DefaultModel();
public void PageLoad(HttpContext context)
{
if (!string.IsNullOrEmpty(context.Request.Form["btn_Add"]))
btn_Add_Click();
View(model);
}
private void btn_Add_Click()
{
model.PageTitle = "btn_Add Button Clicked";
}
Note. After running the program and compiling the aspx pages by Code-Behind, your program will no longer refer to any aspx files. If the scale of the program you are building is high or you need to act dynamically, using Code-Behind will definitely give you more freedom. If the scale of the program is low, using Code-Behind will simplify your program, and you will generate faster and more understandable code.
The following example shows the power of Code-Behind
aspx page
<%@ Page Controller="YourProjectName.wwwroot.DefaultController" Model="YourProjectName.wwwroot.DefaultModel" %><!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title><%=model.PageTitle%></title>
</head>
<body>
<%=model.LeftMenuValue%>
<div class="main_content">
<%=model.MainContentValue%>
</div>
<%=model.RightMenuValue%>
</body>
</html>
Controller class
using CodeBehind;
namespace YourProjectName.wwwroot
{
public partial class DefaultController : CodeBehindController
{
public DefaultModel model = new DefaultModel();
public void PageLoad(HttpContext context)
{
model.PageTitle = "My Title";
CodeBehindExecute execute = new CodeBehindExecute();
// Add Left Menu Page
context.Request.Path = "/menu/left.aspx";
model.LeftMenuValue = execute.Run(context);
// Add Right Menu Page
context.Request.Path = "/menu/right.aspx";
model.RightMenuValue = execute.Run(context);
// Add Main Content Page
context.Request.Path = "/pages/main.aspx";
model.MainContentValue = execute.Run(context);
View(model);
}
}
}
Each of the pages is left.aspx, right.aspx, and main.aspx can also call several other aspx files; these calls can definitely be dynamic, and an add-on can be executed that the kernel programmers don't even know about.
Enjoy Code-Behind, but be careful not to loop the program! (Don't call pages that call the current page).
What power does Code-Behind give you while running the program?
Accessing hypertext contents of pages and replacing some values before calling in other pages.
Microsoft usually ties your hands, so you cannot create a dynamic system.
By using the default architecture of Microsoft's ASP.NET Core, you will face some very big challenges. Creating a system with the ability to support plugins that both provides security and does not loop, and can call other pages on your pages is very challenging.
Suppose you have created an application using the default ASP.NET Core cshtml that has a main page that includes a right menu and a left menu. As shown in the code above, can you change the values of these menus to Fill the dynamic form with cshtml pages and replace the values obtained from the pages? It is definitely possible, but it is difficult.
Code-Behind will not even refer to the physical aspx file to call the aspx pages and will only call a method.
How do you manage events in ASP.NET Core?
For example, a route from your program requires several methods to be executed, and these methods do not exist in the core of your program! This work can be blinded with the default cshtml of .NET, but it is difficult.
For example, we should have an event before the request to the search page and not allow the user to do more than 2 searches per minute. Using Code-Behind, we only need to check an aspx page, then reject or allow the search request.
