This article shows how to create a Class Library project and include it in a web application project. ASP.NET is part of the Microsoft .NET Framework. To build ASP.NET pages, you need to take advantage of the features of the .NET Framework. A Class Library is one of them. A Class Library contains one or more classes that can be called on to perform specific actions. Creating a Class Library makes a DLL that can be used for reusability.
Creating Class Liberary
Now open the Visual Studio and select "File" -> "New" -> "Project..." -> "Class Library". The following code will be generated:
![Class Library1.jpg]()
Now click on the "Ok" button. The Solution Explorer contains C# classes (class.cs) in your project. Now replace the default code (shown above) with the following code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ClassliberaryDemo
{
public class PersonalDetail
{
private string _firstname;
private string _lastname;
private string _Email;
private long _PhoneNumber;
public string FirstName
{
get { return _firstname; }
set { _firstname = value; }
}
public string LastName
{
get { return _lastname; }
set { _lastname = value; }
}
public string Email
{
get { return _Email; }
set { _Email = value; }
}
public long PhoneNumber
{
get { return _PhoneNumber; }
set { _PhoneNumber = value; }
}
}
}
Now build this project. After building this project, you will see ClassLibrary1.dll in your project's bin/debug directory.
![Class-Library2.jpg]()
Now open the Visual Studio again and select "File" -> "New" -> "Project..." -> "ASP.NET web application"
![Class-Library3.jpg]()
Now add the reference of the preceding created DLL. To add a reference right-click on the project then seelct "Add Reference".
![Class-Library4.jpg]()
Now browse to the ClassLibrary1.dll file and add it to the application.
![Class-Library5.jpg]()
Use the following procedure to call the properties of your component.
Using namespace
Add a using statement (as in the following) for ClassliberaryDemo to the beginning of your project.
using ClassliberaryDemo;
Create an Object of the "PersonalDetail" class, as in the following:
PersonalDetail PD = new PersonalDetail();
Now Calling Properties
![Class-Library6.jpg]()