Video ERD Normalized

Here is the diagram that we did in class for the practices for chapter 5

Loops arrays, while

here is the code for the day. I may return to it to add comments later">

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Shopping
{
    class Program
    {
        //we need to create two arrays
        //one for the items
        //one for the prices
        //we will prompt the user how many items
        //they want to enter
        //Then we will enter items and prices
        //into the two arrays
        //we will sum the prices and add tax
        //we will display a summary information
        //then we will ask if they want to enter 
        //another list. If they say yes we
        //will do it again, if no we will exit
        int number=0;

        static void Main(string[] args)
        {
            Program p = new Program();
            p.Display();
        }

        private void Display()
        {
            //loop the program as long as the user says yes
            string choice = "yes";
            while (choice == "yes" || choice == "y")
            {
                //this changes the console background to blue
                Console.BackgroundColor = ConsoleColor.DarkBlue;
                Console.Clear();
                
                //call methods
                GetNumberOfItems();
                CreateShoppingArray();
                CreatePricesArray();
                FillArrays();
                Console.WriteLine("do you want to contine with another list--yes or no");
                choice = Console.ReadLine();
                choice = choice.ToLower();
            }
            //Console.ReadKey();
        }

        //get the number of items
        private void GetNumberOfItems()
        {
            Console.WriteLine("How many items do you want to enter?");
            number = int.Parse(Console.ReadLine());
         
        }
        //create the two arrays
        private string[] CreateShoppingArray()
        {
            string[] items = new string[number];
            return items;
        }

        private double[] CreatePricesArray()
        {
            double[] prices = new double[number];
            return prices;
        }

        //this prompts the user and fills the arrays
        private void FillArrays()
        {
            string[] shoppingItems = CreateShoppingArray();
            double[] itemPrices = CreatePricesArray();

            for (int i = 0; i < shoppingItems.Length; i++)
            {
                Console.WriteLine("Enter the item");
                shoppingItems[i] = Console.ReadLine();
                Console.WriteLine("Enter the item price");
                itemPrices[i] = double.Parse(Console.ReadLine());
              
            }//end for
            CalculateResults(shoppingItems, itemPrices);
        }//end fill array

        private void CalculateResults(string[] shoppingList, double[] itemCost)
        {
            Console.WriteLine("*****************************\n");
            double total = 0;
            for (int i = 0; i < itemCost.Length; i++)
            {
                //same as total=total + itemCost[];
                total += itemCost[i];
            }

            Console.WriteLine("Your Items");
            for(int i=0;i< shoppingList.Length;i++)
            {
                Console.WriteLine(shoppingList[i] + "\t\t" + itemCost[i].ToString("c"));
            }

            Console.WriteLine("Total {0:C}", total);

        }
    }
}

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Here is the earlier code

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace WhileLoops
{
    class Program
    {
        static void Main(string[] args)
        {
            Program p = new Program();
            //uncomment the method you want to run
            //comment the ones you don't want to run

            p.ForLoopReview();
            p.WhileLoopExample();
            p.DoLoopExample();
            Console.ReadKey();
        }


        private void ForLoopReview()
        {
            string[] languages=new string[4];
            languages[0] = "C++";
            languages[1] = "C#";
            languages[2] = "Java";
            languages[3] = "php";

            for (int i = 0; i < languages.Length; i++)
            {
                Console.WriteLine(languages[i]);
            }//end for
        }//end for loop review

        private void WhileLoopExample()
        {
            int x = 6;
            Console.WriteLine("While Loop OutPut");
            while (x < 6)
            {
                Console.WriteLine(x);
                x++;
            }
        }//end while loop example

        private void DoLoopExample()
        {
            int x = 6;
            Console.WriteLine("Do loop output");
            do
            {
                Console.WriteLine(x);
                x++;
            } while (x < 6);
        }
    }//end class
}//end namespace

Venue Tracking Database Take one

Here is the diagram we did in class:

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Loops and arrays 1

Here is a first look at creating arrays and for loops:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ArraysandLoops
{
    class Program
    {
        static void Main(string[] args)
        {
            Program p = new Program();
            p.Run();
            Console.ReadKey();
        }

        private void Run()
        {
           
            DisplayArray();
            InitializedArray();
        }

        private string[] CreateArray()
        {
            //declare an array of strings
            string[] cheese = new string[5];
            return cheese;
           // FillArray(cheese);
        }

        private string[] FillArray()
        {
            //create an array variable to store
            //the array returned by create array
            string[] queso = CreateArray();
            //this loop starts at zero, and loops
            //until it is less than the length of the array (5)
            //i++ increments the counter by 1
            for (int i = 0; i < queso.Length; i++)
            {
                Console.WriteLine("enter a cheese");
                string cheeseName = Console.ReadLine();
                //assigns it to the current index of the array
                queso[i] = cheeseName;
            }//end for loop

            return queso;
        }//end fill Array

        private void DisplayArray()
        {
            
            string[] fromage = FillArray();
            Console.WriteLine("************************\n");
   
            for (int i = 0; i < fromage.Length; i++)
            {
                Console.WriteLine(fromage[i]);
            }//end for

            Console.WriteLine(fromage[3]);
        }//end displayArray

        private void InitializedArray()
        {
            //create an array of integers and 
            //assign them immediately
            int[] numbers = new int[] { 1, 3, 5, 6, 8, 2 };
            //loop through the array to display them
            for (int i = 0; i < numbers.Length; i++)
            {
                Console.WriteLine(numbers[i]);
            }
        }




    }//end class
}//end namespace

Here is the example of summing and averaging arrays

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SumandAverageArrays
{
    class Program
    {
        static void Main(string[] args)
        {
            Program p = new Program();
            p.CreateArray();
            Console.ReadKey();
        }

        private void CreateArray()
        {
            double[] numbers = new double[] { 2, 3.21, 4, 5.234, 1.2, 6 };
            GetSum(numbers);

        }

        private void GetSum(double[] numberArray)
        {
            double sum=0;
            for(int i=0;i<numberArray.Length;i++)
            {
                //+= equivalent to sum = sum + numberarray[i]
                sum+=numberArray[i];
            }

            double average = sum / numberArray.Length;
            Console.WriteLine("The sum is {0}", sum);
            Console.WriteLine("The average is {0}", average);
            //these built in methods do the same thing
            Console.WriteLine("**********************");
            Console.WriteLine(numberArray.Sum());
            Console.WriteLine(numberArray.Average());
        }
    }
}

Beginning Database Design

We began by looking at Visio 2010. We drug an Entity onto the grid and use the properties window to Name it DVD. Then we assigned a primary Key and some fields. We Determined that actor was a multi-valued attribute, meaning that every DVD probably has many Actors, so we broke it into its own entity.

There are Three Kinds of relationships:
*One to One, where each record in the primary key is related to no more than 1 record in the child table
*One to Many, where each record in the primary key table can be related to zero or several records in the child table
*Many To Many, where each record in the primary key table can be related to any number of records in the child table, and each record in the child table can be related to any number of records in the parent table. These must be resolved by adding a linking table

Next we determined that there is a many to many relationship between DVD and Actor.Here is the Diagram

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More if and else if

This is the code that is part of assignment 3

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Medicare
{
    class Program
    {
        static void Main(string[] args)
        {
            //load the program 
            Program p = new Program();
            //call the display method
            p.Display();
            //pause it
            Console.ReadKey();
        }

        private void Display()
        {
            //get the inputs
            Console.WriteLine("Enter Your pay rate");
            double rate = double.Parse(Console.ReadLine());
            Console.WriteLine("Enter your hours");
            double hours = double.Parse(Console.ReadLine());

            //call the CalculateGross method and store the value
            //it returns in the local variable gross
            double gross = CalculateGrossPay(rate, hours);
            Console.WriteLine("Your gross pay is {0:C}", gross);
            //call the method to CalculateMedicare
            double med = CalculateMedicare(gross);
            Console.WriteLine("Your Medicare Deduction is {0:C}", med);
        }

        private double CalculateGrossPay(double rate, double hours)
        {
            //this method calcuates pay 
            //it takes overtime into account
            double grossPay=0;
            if (hours > 40)
            {
                grossPay = rate * (40 + ((hours - 40) * 1.5));
            }
            else
            {
                grossPay = rate * hours;
            }

            return grossPay;
        }//end calculateGrosspay

        private double CalculateMedicare(double gross)
        {
            double medicare = 0;
            //5000 > .2
            //2000 to 4999 .1
            //1999 or less .03
            //uses and if, else if to calculate percentages
            if (gross >= 5000)
            {
                medicare = gross * .2;
            }
            else if (gross >= 2000)
            {
                medicare = gross * .1;
            }
            else
            {
                medicare = gross * .03;
            }

            return medicare;
        }
    }
}

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Here are the other if, else if examples

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Medicare
{
    class Program
    {
        static void Main(string[] args)
        {
            //load the program 
            Program p = new Program();
            //call the display method
            p.Display();
            //pause it
            Console.ReadKey();
        }

        private void Display()
        {
            //get the inputs
            Console.WriteLine("Enter Your pay rate");
            double rate = double.Parse(Console.ReadLine());
            Console.WriteLine("Enter your hours");
            double hours = double.Parse(Console.ReadLine());

            //call the CalculateGross method and store the value
            //it returns in the local variable gross
            double gross = CalculateGrossPay(rate, hours);
            Console.WriteLine("Your gross pay is {0:C}", gross);
            //call the method to CalculateMedicare
            double med = CalculateMedicare(gross);
            Console.WriteLine("Your Medicare Deduction is {0:C}", med);
        }

        private double CalculateGrossPay(double rate, double hours)
        {
            //this method calcuates pay 
            //it takes overtime into account
            double grossPay=0;
            if (hours > 40)
            {
                grossPay = rate * (40 + ((hours - 40) * 1.5));
            }
            else
            {
                grossPay = rate * hours;
            }

            return grossPay;
        }//end calculateGrosspay

        private double CalculateMedicare(double gross)
        {
            double medicare = 0;
            //5000 > .2
            //2000 to 4999 .1
            //1999 or less .03
            //uses and if, else if to calculate percentages
            if (gross >= 5000)
            {
                medicare = gross * .2;
            }
            else if (gross >= 2000)
            {
                medicare = gross * .1;
            }
            else
            {
                medicare = gross * .03;
            }

            return medicare;
        }
    }
}

First Ifs (Selection) and a bit of assignment 2

Here is the piece of Assignment Two

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication3
{
    class Program
    {

        //declare a constant
        const double MEDICARE = .03;

        static void Main(string[] args)
        {
            Program p = new Program();
            //call show pay
            p.ShowNetPay();
           
        }

        private double GrossPay(double hours, double rate)
        {
            //we pass hours and rate into the method and then
            //multiply them
            //not worried about overtime at this point
            return hours * rate;
        }

        private double CalculateMedicare(double gross)
        {
            //pass in gross and multiply it by constant
            return gross * MEDICARE;
        }

        private void ShowNetPay()
        {
            //enter the hours and rate
            Console.WriteLine("Enter hours worked");
            double hours = double.Parse(Console.ReadLine());
            Console.WriteLine("Enter the rate of Pay");
            double rate = double.Parse(Console.ReadLine());

            //get the gross pay by calling the method
            //and storing the value it returns
            double grosspay = GrossPay(hours, rate);
            //call the method for medicare
            double med = CalculateMedicare(grosspay);

            //do the calculation for net pay
            double netpay = grosspay - (med );
            //Display the result
            Console.WriteLine("Your net pay is {0}", netpay);
        }
    }
}

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Here is the sample with if statements

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace SelectionExamples
{
    class Program
    {
        //first we will make a method to determine
        //if a number even
        //we also introduce tryParse
        static void Main(string[] args)
        {
            //initialize the rest of the class
            Program p = new Program();
            //call the TestNumber method
            p.TestNumber();

            //pause the program to wait for a key stroke
            Console.ReadKey();
        }

        private void TestNumber()
        {
            //this gets an integer number from the user
            //if it is not a valid integer it propmpts the user
            //to start again with a valid integer number

            //declare a variable with a default of zero
            //the TryParse out parameter will assign
            //a new value to this variable
            int num = 0;
            //asl for a number from the user
            Console.WriteLine("Enter an Integer");
            //the tryParse returns true or false (a boolean)
            //if the string on the console can be parsed as an integer
            //it returns true and assigns the value to num,
            //if not it returns false
            bool isInt = int.TryParse(Console.ReadLine(), out num);

            //if it is false prompt them to enter a valid number
            if (isInt == false)
            {
                Console.WriteLine("Make sure you enter an integer");
                return; //end the method
            }

            //if it is true it will continue to execute the code
            //we call the TestForEven number,
            //and pass the num we got from the console
            //then we store the 
            //result ("odd" or "even") in the variable numType
            string numType = TestForEven(num);

            //print out the value of numType
            Console.WriteLine(numType);
        }

        private string TestForEven(int number)
        {
            //create a variable with a default value
            //of odd
            string result = "odd";
            //if then the condition in parenthesis
            //must resolve to true or false
            if (number % 2 == 0) //== means equal
            {
                result = "even";
            }

            //return the result
            return result;
        }
    }
}

Methods and Operators

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication3
{
    /******************
     * + is addition
     * - is subtraction
     * * is multipication
     * / is division (if both sides are integer then any decimal part is dropped)
     * % modulus, returns the remainder from an integer division
     * follows same order of operations as algebra
     * all multiplications and divisions first left to right
     * all substractions and additons left to write
     * but what is in parenthesis is first
     * embedded parenthesis from inside out 
     * */
    class Program
    {
        private double total;
        private const double TAX = .095;

        static void Main(string[] args)
        {
            Program p = new Program();
            //p.GetPrice();
            //p.DisplayTotal();
            int quotient = p.IntegerDivision(8, 3);
            Console.WriteLine("the quotient is {0}", quotient);
            int modulus = p.GetTheModulus(8, 3);
            Console.WriteLine("the remainder is {0}", modulus);
           Console.ReadKey();
        }

        private void GetPrice()
        {
            Console.WriteLine("Enter the Price");
            double price = double.Parse(Console.ReadLine());

            total=GetTotal(price);
        }

        private double GetTotal(double pr)
        {
            return  pr * (1 + TAX);
        }

        private void DisplayTotal()
        {
            Console.WriteLine("Your total is {0:c}",total);
        }

        private int IntegerDivision(int number1, int number2)
        {
            return number1 / number2;
        }

        private int GetTheModulus(int num1, int num2)
        {
            return num1 % num2;
        }
    }
}

Gas Mileage with Methods

Here is the Gas Mileage calculator without methods that we did as the first assignment

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace GasMileageCalculator
{
    /*********************
     * This program will calculate miles per
     * gallon and price per mile
     * Steve Conger 9/27/2012
     * *********************/
    class Program
    {
        static void Main(string[] args)
        {
            //get inputs 
            //prompt user 
            Console.WriteLine("Enter the Total Mileage");//write prompt
            int miles = int.Parse (Console.ReadLine());

            Console.WriteLine("Enter the total Gallons");
            int gallons = int.Parse(Console.ReadLine());

            Console.WriteLine("Enter the Price Per Gallon");
            double price = double.Parse(Console.ReadLine());

            //Calculate the outputs

            double milesPerGallon = (double) miles / gallons;
            double pricePerMile = price / milesPerGallon;

            // Display outputs
            Console.WriteLine();
            Console.WriteLine("Your miles per gallon is {0:F2} \n", milesPerGallon);
            
            Console.WriteLine("The price per mile is {0:c}", pricePerMile);

            Console.ReadKey();



        }
    }
}

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Methods

A few words about methods:

Methods are ways of braking up code into more manageable blocks.

Ideally each method does one thing. It can be one complicated thing involving several lines of code, but still one thing.

In order to execute a method must be called. You call a method by using its name and providing any required parameters. (See Example Two.)

Methods can only be called from other methods. At least one method must be called from the Main method to start the program

Methods can be private meaning they can only be seen by other methods in the current class, or they can be public meaning they can be seen by other classes and programs. (there are other options in between such as protected.)

Methods can be void (as in the first example) meaning that they return nothing to the calling method or they can return a value(see example two)

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Here is the code from class. This version makes the variables have class scope, which means they can be accessed by any of the methods in the class.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;



namespace GasMileageCalculatorWithMethods
{
    class Program
    {
        /*
         * get inputs
         * calculate miles per Gallon
         * calculate price per mile
         * Display the outputs
         */
        //declaring variables with class scope
        int miles;
        int gallons;
        double price;
        
        static void Main(string[] args)
        {
            //The Program class is not yet loaded
            //into memory, though the Main method is
            //because it is static, so we have to
            //load the class into memory with the new
            //keyword
            Program p = new Program();
            p.CallMethods();
           
        }//end main



        private void GetMiles()
        {
            Console.WriteLine("Please Enter the total Miles");
            miles = int.Parse(Console.ReadLine());
        }//end GetMiles

        private void GetGallons()
        {
            Console.WriteLine("Please Enter the total Gallons");
            gallons = int.Parse(Console.ReadLine());
        }//end getGallons

        private void GetPricePerGallon()
        {
            Console.WriteLine("Please Enter the price per Gallon");
            price= double.Parse(Console.ReadLine());
        }

        private double CalculateMilesPerGallon()
        {
            double mpg;
            mpg=miles / (double)gallons;
            return mpg;
        }

        private double CalculateCostPerMile()
        {
            return price / CalculateMilesPerGallon();
        }

        private void DisplayResults()
        {
            Console.WriteLine("Your Miles per Gallon is {0:F2}", CalculateMilesPerGallon());
            Console.WriteLine("The cost per mile is {0:C}", CalculateCostPerMile());
            Console.ReadKey();
        }

        private void CallMethods()
        {
            GetMiles();
            GetGallons();
            GetPricePerGallon();
            DisplayResults();
        }

    }//end class
}//end namespace

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Here is a second example of the same program. Instead of making variables with class level scope, the variables are passed as parameters to the appropriate methods

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace GasMileageCalculatorMethods
{
    class Program
    {
        //This program use methods with parameters
        // to calculate gas mileage
       
        double price;

        static void Main(string[] args)
        {
            //explain this
            Program p = new Program();
            p.Display();
        }

        private void Display()
        {
            //calling methods
            GetInputs();
            Console.ReadKey();
        }

        private void GetInputs()
        {
            //this method could be broken up as we did
            //in the example above
            Console.WriteLine("Enter the total Miles");
            int miles = int.Parse(Console.ReadLine());
            Console.WriteLine("Enter the Total gallons");
            double gallons = double.Parse(Console.ReadLine());

            //call and pass values
            double milesPerGallon=CalculateMileage(miles, gallons);

            Console.WriteLine("Enter the price per gallon");
            price = double.Parse(Console.ReadLine());

            double pricePerMile = CalculatePrice(price, milesPerGallon);

            DisplayOutputs(milesPerGallon, pricePerMile);


        }

        private double CalculateMileage(int m, double gals)
        {
            //explain return
            return m / gals;
        }

        private double CalculatePrice( double pr, double mpg)
        {
            return pr  / mpg;
        }

        private void DisplayOutputs(double milesPerGallon, double pricePerMile)
        {
            //explain calling the method 
            Console.WriteLine("You got {0:F2} miles per gallon", milesPerGallon);
            Console.WriteLine("The price per mile was {0:C}", pricePerMile);
        }
    }
}