ExceptionHandling

[MrBlack]

in my code Devide method is not working it gives an error "ExceptionHandling.Program.Devide(int, int)': not all code paths return a value"

When i change public int Devide method in to void,the programe is workig , plz explain me what is the wrong with my code, im new to programming , plz help me

class Program
    {
        public int Devide(int a, int b)
        {
            try
            {
                int k;
                k = a / b;
                return k;
            }

            catch (DivideByZeroException e)
            {
                Console.WriteLine(e.Message);
            }   

        }
        static void Main(string[] args)
        {
           int c;

            Program p = new Program();
           c= p.Devide(8,0);
          
            
        }
    }

[ddanbe]

You should check that the divisor (in your case variable b) is not zero.
You cannot divide by zero. you cannot do that in math, so why do you think a computer, which consists mainly of silicon(from sand), copper and plastic, is able to do that?
If you use void for a method, that method returns nothing. So don't use it if you want your method to return something.

[MrBlack]

You should check that the divisor (in your case variable b) is not zero.
You cannot divide by zero. you cannot do that in math, so why do you think a computer, which consists mainly of silicon(from sand), copper and plastic, is able to do that?
If you use void for a method, that method returns nothing. So don't use it if you want your method to return something.

yes i know we cant Divide some value bye zero,in math it will give infinity, thats why i use a DividebyZeroException(or Exception ) ,in line 8 it throws exception it should cath in 12,but this is not work for in if i int return type for the method, but try to do this exception handling with using a void it perfectly work,
Does Exception only work for void

here is the working code

class Program
    {
        public void Devide(int a, int b)// i use void not int
        {
            try
            {
                int c;
                c = a / b;
                Console.WriteLine(c);  
            }

            catch(DivideByZeroException e)
            {
                Console.WriteLine(e.Message);
            }
        }
        static void Main(string[] args)
        {
            Program p = new Program();
             p.Devide(4,0);
          
        }
    }

Why i cant use int and why i cant return some value

[ddanbe]

Try this:

class Program
    {
        static void Main(string[] args)
        {
            int result;
            result = Devide(4, 0); //calculate result
            Console.WriteLine(result); //write result
            Console.ReadKey(); //keep console on screen in debug mode
        }

         static int Devide(int a, int b)// i use void not int 
             // changed it to static so I don't need object reference
             // kept your spelling of the word divide
         {            
             try            
             {                
                 int c;                
                 c = a / b;
                 return c;
                 //These three lines could be replaced by : return a / b;
                 //Console.WriteLine(c);  //do this outside the method            
             }             
             catch(DivideByZeroException e)            
             {                
                 Console.WriteLine(e.Message); 
                 return -1; //must return something, some error code?
             }        
         }
    }

[MrBlack]

Try this:

class Program
    {
        static void Main(string[] args)
        {
            int result;
            result = Devide(4, 0); //calculate result
            Console.WriteLine(result); //write result
            Console.ReadKey(); //keep console on screen in debug mode
        }

         static int Devide(int a, int b)// i use void not int 
             // changed it to static so I don't need object reference
             // kept your spelling of the word divide
         {            
             try            
             {                
                 int c;                
                 c = a / b;
                 return c;
                 //These three lines could be replaced by : return a / b;
                 //Console.WriteLine(c);  //do this outside the method            
             }             
             catch(DivideByZeroException e)            
             {                
                 Console.WriteLine(e.Message); 
                 return -1; //must return something, some error code?
             }        
         }
    }

Thanks a lot ddanbe i found the error in my code , i didnt return -1 ; why do we return somgthing, Can you explain plz

[ddanbe]

Your code did work, because you did declare your method to return nothing, by using the keyword void . Void comes in handy when you want your method to return nothing. Say your program wants to explain something to a user, you would use a void method that uses a lot of Console.WriteLines etc. to write to the console.
But if you are performing a calculation, like with your Divide method, you should return the result of that calculation. If you devise such a method you must make sure that all code paths inside your method end in a return of whatever datatype your method returns to the main program.

[MrBlack]

Your code did work, because you did declare your method to return nothing, by using the keyword void . Void comes in handy when you want your method to return nothing. Say your program wants to explain something to a user, you would use a void method that uses a lot of Console.WriteLines etc. to write to the console.
But if you are performing a calculation, like with your Divide method, you should return the result of that calculation. If you devise such a method you must make sure that all code paths inside your method end in a return of whatever datatype your method returns to the main program.

Thanks a lot ddanbe, i understood Thanks again