Expression bodied members in C Sharp 7.0

C# 6.0
 
Expression bodied Methods
Expression bodied Properties
 
C# 7.0
 
Expression bodied constructor
 
Expression bodied destructor
 
Expression bodied getters
Expression bodied setters
Expression bodied Events.

 

Expression bodied Methods:

Let us learn the Previous Release of Expression bodied Method in C sharp 6.0.

Sample Syntax :

public string GetUserDetails

() => $ "{UserId} + {UserName} + {EmailId} + {ContactNumber}"; 

 Example:

class User

    {    
        public int UserId { get; set; }  
        public string UserName { get; set; }  
        public string EmailId { get; set; }  
        public string ContactNumber { get; set; }  
        public string GetUserDetails() => $"{UserId} + {UserName} + {EmailId} + {ContactNumber}"; 

    }


    class Program
    {       
static void Main(string[] args)        {
            User obj = new User();
            obj.UserId = 001;
            obj.UserName = "Rajakonda Uday Kumar";
            obj.EmailId = "rajakondauday@gmail.com";
            obj.ContactNumber = "123456";
            Console.WriteLine(obj.GetUserDetails());
            Console.ReadLine();
        }
    }

Output:

 

There might be the situation where we want to override the ToString method in that case
class User
    {   
        public int UserId { get; set; } 
        public string UserName { get; set; } 
        public string EmailId { get; set; } 
        public string ContactNumber { get; set; } 
        public string GetUserDetails() => $"{UserId} + {UserName} + {EmailId} + {ContactNumber}";
        public override string ToString() => $"{UserId} + {UserName} + {EmailId} + {ContactNumber}";
    }
    class Program
    {
        static void Main(string[] args)
        {
            User obj = new User();
            obj.UserId = 001;
            obj.UserName = "Rajakonda Uday Kumar";
            obj.EmailId = "rajakondauday@gmail.com";
            obj.ContactNumber = "123456";
            Console.WriteLine(obj.ToString());
            Console.ReadLine();
        }
    }

 

Expression Bodied Properties:

class User
    {   
        public int UserId { get; } = 0001;
        public string UserName { get; } = "Rajakonda Uday Kumar";
        public string EmailId { get;} = "rajakondauday@gmail.com";
        public string ContactNumber { get; } = "123456";
        public string GetUserDetails() => $"{UserId} + {UserName} + {EmailId} + {ContactNumber}";
        public override string ToString() => $"{UserId} + {UserName} + {EmailId} + {ContactNumber}";
    }
    class Program
    {
        static void Main(string[] args)
        {
            User obj = new User();
            Console.WriteLine(obj.ToString());
            Console.ReadLine();
        }
    }

In C Sharp 7.0

 

Expression bodied constructor

 class User
    {
        public int UserId { get; } = 0001;
        public string UserName { get; } = "Rajakonda Uday Kumar";
        public string EmailId { get;} = "rajakondauday@gmail.com";
        public string ContactNumber { get; }
        public User()=> ContactNumber= "99898955555";
    }

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(new User().ContactNumber);
            Console.ReadLine();
        }
    }

Output:

 

Expression bodied destructor

class User
    {
        public int UserId { get; } = 0001;
        public string UserName { get; } = "Rajakonda Uday Kumar";
        public string EmailId { get;} = "rajakondauday@gmail.com";
        public string ContactNumber { get; }
        public User()=> ContactNumber= "99898955555";
        ~User() => Console.WriteLine("Destructor Method");
    }
    class Program
    {
        static void Main(string[] args)
        {
            Details();
            GC.Collect();
            Console.ReadLine();
        }
        public static void Details()
        {
            Console.WriteLine(new User().ContactNumber);
            User user = new User();
        }
    }

Expression bodied getters & setters

class User
    {
        public Dictionary<int, string> UserList = new Dictionary<int, string>();
        public int UserId { get; } = 101;
        public string UserName { get; } = "Rajakonda Uday Kumar";
        public string EmailId { get;} = "rajakondauday@gmail.com";
        public string ContactNumber { get; }
        public string UserDetails
        {   get => UserList[UserId]; 
            set => UserList[UserId] = value; 
         }
    }
    class Program
    {
        static void Main(string[] args)
        {
            User obj = new User();
            obj.UserList.Add(101, "A");
            obj.UserList.Add(102, "B");
            Console.WriteLine(obj.UserDetails);
            Console.ReadLine();
        }
    }

Examples:

class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine($" {new Employee().EmployeeDetail()}");
            Console.ReadLine();
        }
    }
    class Employee
    {
        int empId { get; } = 101;
        string Name { get; } = "ABC";
        string Address { get; } = "Hyderabad";
        double Salary { get; } = 1000;
        public double HRA() => (Salary * 40) / 100;
        public string EmployeeDetail() => $"EmployeeId: {empId}\n EmployeeName: {Name}\nEmployeeAddress: {Address}\nEmployeeHRA: {HRA()}";
    }

 

Output:

 

2) Example:

class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine($" {new Employee().EmployeeDetail()}");
            Console.ReadLine();
        }
    }

    class Employee
    {
        int empId { get; } = 101;
        string Name { get; } = "ABC";
        string Address { get; } = "Hyderabad";
        double Salary { get; } = 1000;
        public Employee() => Salary = 1000;

        public double HRA() => (Salary * 40) / 100;
        public string EmployeeDetail() => $"EmployeeId: {empId}\n EmployeeName: {Name}\nEmployeeAddress: {Address}\nEmployeeHRA: {HRA()}";

        ~Employee() => Console.WriteLine("\n Destructor");
    }