C# Beginner Program Pass an Array to a Method

Question

New c# learner, this program is to input grades and then figure the average. However, I want to use specific student ID numbers (ie 3345, 6654, etc.) rather than the looped numbers as IDs. How can I edit this code to reflect this? Thanks in advance.

 class ClassScores
 {
 private Score[] scores;
 private int index;
 public ClassScores(int n)
 {
 scores = new Score[n];
 index = 0;
 }
 public void addScore(Score obj)
 {
 scores[index] = obj;
 index++;
 }
 public Score highScore()
 {
 Score obj = scores[0];
 for (int i = 0; i < index; i++)
 {
 if (scores[i].getGrade() > obj.getGrade())
 {
 obj = scores[i];
 }
 }
 return obj;
 }
 public double average()
 {
 int sum = 0;
 for (int i = 0; i < index; i++)
 {
 sum += scores[i].getGrade();
 }
 return (sum / (double)(scores.Length));
 }
 }
}
 class Score
 {
 private int id;
 private int grade;
 public Score(int studentID, int studentGrade)
 {
 id = studentID;
 grade = studentGrade;
 }
 public void setId(int studentID)
 {
 id = studentID;
 }
 public void setGrade(int score)
 {
 grade = score;
 }
 public int getGrade()
 {
 return grade;
 }
 public int getId()
 {
 return id;
 }
 }
 class Program
 {
 static void Main(string[] args)
 {
 ClassScores classOne = new ClassScores(6);
 for (int i = 1; i <= 6; i++)
 {
 Console.Write("Enter Score for Student " + i + ": ");
 int grade = Convert.ToInt32(Console.ReadLine());
 Score classTwo = new Score(i, grade);
 classOne.addScore(classTwo);
 }
 Console.WriteLine("\n\n Average Score: " + classOne.average());
 Score high = classOne.highScore();
 Console.WriteLine("\n\n Student with id: " + high.getId() + " has a Highest Score: " + high.getGrade() + "\n\n");
 Console.Read();
 }
 }

It will need an array of six different student ID numbers.

• Dour High Arch: You have several problems here, try reducing your code and question to one problem at a time.
• teestokes12: Okay, now there is a single question. I wouldn't know how to cut down the code without compromising the question.
• Alexei Levenkov: Side note: learning C# using Java book? Look into learn.microsoft.com/en-us/dotnet/csharp/programming-guide/… (or in properties in general)

Answer 1

You can change your for loop to prompt the user to enter the Student ID. You can then pass that to the Score class constructor:

for (int i = 1; i <= 6; i++)
{
 Console.Write("Enter Student ID:");
 int id = Convert.ToInt32(Console.ReadLine());
 Console.Write("Enter Score for Student " + id + ": ");
 int grade = Convert.ToInt32(Console.ReadLine());
 Score classTwo = new Score(id, grade);
 classOne.addScore(classTwo);
}

EDIT

If you already have your Student ID's in an array you can loop over that array:

int[] studentIds = new[] { 3524, 4321, 546, 7896, 4327, 123 };
ClassScores classOne = new ClassScores(studentIds.Length);
foreach(int id in studentIds)
{
 Console.Write("Enter Score for Student " + id + ": ");
 int grade = Convert.ToInt32(Console.ReadLine());
 Score classTwo = new Score(id, grade);
 classOne.addScore(classTwo);
}

We have changed the for loop to a foreach which will loop over each item in the array and retrieve each value

If you still want to use a for loop instead then you can use the loop variable to get the ID from the array - remember arrays are zero based so you need to loop from zero to the length of the array:

for (int i = 0; i < studentIds.LEngth; i++)
{
 int id = studentIds[i];
 ...
}

• teestokes12: This is helpful! I do need it to already have the ID's stored in an array, though.
• Simply Ged: @teestokes12 I've updated my answer to include an array of student ids - you didn't put that in your original question so I've had to guess the numbers