数组以及如何更新,删除和检索条目

时间:2013-10-17 22:28:28

标签: c# arrays console-application

嗨,我有一个作业,我必须创建一个程序,其中包含三个数组,一个用于人名,一个用于得分,一个用于玩家数,现在我已经拥有了所有数组事情已经完成但我很困惑,我将如何检索条目,更新条目或删除条目到目前为止,我有工作的选项是创建播放器,列表播放器和退出其他两个我不知道该怎么做,正确方向的一些指导真的很有帮助,谢谢你。

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

namespace PlayerSystem6
{
    class Program
    {
        static void Main(string[] args)
        {
            //The MAXPLAYERS constant is the physical table size
            const Int32 MAXPLAYERS = 23;

            //Declare the player tables
            Int32[] playerNumbers = new Int32[MAXPLAYERS];
            String[] playerLastNames = new String[MAXPLAYERS];
            Int32[] playerPoints = new Int32[MAXPLAYERS];

            //Keep track of the actual number of players (i.e. logical table size)
            Int32 playerCount = 0;

            //Main Driver
            char menuItem;
            Console.WriteLine("Welcome to the player system...\n");
            menuItem = GetMenuItem();
            while (menuItem != 'X')
            {
                ProcessMenuItem(menuItem, playerNumbers, playerLastNames, playerPoints, ref playerCount, MAXPLAYERS);
                menuItem = GetMenuItem();
            }
            Console.WriteLine("\nThank you, goodbye");
            Console.ReadLine();
        }

        //Returns either a 'C', 'R', 'U', 'D', 'L', or 'X' to the caller
        static char GetMenuItem()
        {
            char menuItem;
            DisplayMenu();
            menuItem = char.ToUpper(char.Parse(Console.ReadLine()));
            while (menuItem != 'C'
                && menuItem != 'L' && menuItem != 'X')
            {
                Console.WriteLine("\nError - Invalid menu item");
                DisplayMenu();
                menuItem = char.ToUpper(char.Parse(Console.ReadLine()));
            }
            return menuItem;
        }

        static void DisplayMenu()
        {
            Console.WriteLine("\nPlease pick an item:");
            Console.WriteLine("C - Create Player");
            Console.WriteLine("R - Retrieve Player");
            Console.WriteLine("U - Update Player");
            Console.WriteLine("D - Delete Player");
            Console.WriteLine("L - List Players");
            Console.WriteLine("X - Exit");
        }

        //Routes to the appropriate process routine based on the user menu choice
        static void ProcessMenuItem(Char menuItem, Int32[] playerNumbers, String[] playerLastNames,
            Int32[] playerPoints, ref Int32 playerCount, Int32 MAXPLAYERS)
        {
            switch (menuItem)
            {
                case 'C':
                    ProcessCreate(playerNumbers, playerLastNames, playerPoints, ref playerCount, MAXPLAYERS);
                    break;
                case 'L':
                    ProcessList(playerNumbers, playerLastNames, playerPoints, playerCount);
                    break;
            }
        }

        //Creates a player in the tables if the array is not already full and the name is not a duplicate
        static void ProcessCreate(Int32[] playerNumbers, String[] playerLastNames,
            Int32[] playerPoints, ref Int32 playerCount, Int32 MAXPLAYERS)
        {
            Int32 number, points;
            String lastName;
            if (playerCount < MAXPLAYERS)
            {
                number = GetPositiveInteger("\nCreate Player: please enter the player's number");
                if (GetPlayerIndex(number, playerNumbers, playerCount) == -1)
                {
                    lastName = GetString("\nCreate Player: please enter the player's last name");
                    points = GetPositiveInteger("\nCreate Player: please enter the player's points");
                    InsertPlayer(number, lastName, points, playerNumbers, playerLastNames, playerPoints, ref playerCount);
                    Console.WriteLine("\nCreate Player: Number - {0}, Name - {1}, Points - {2}, created successfully", number, lastName, points);
                    Console.WriteLine();
                }
                else
                    Console.WriteLine("\nCreate Player: the player number already exists");
            }
            else
                Console.WriteLine("\nCreate Player: the player roster is already full");

        }

        //Inserts the player at the correct location in the tables based on order of 
        //ascending player number. Unless the insert location is at the end, this 
        //requires shifting existing players down in order to make room 
        static void InsertPlayer(Int32 number, String lastName, Int32 points,
            Int32[] playerNumbers, String[] playerLastNames, Int32[] playerPoints,
            ref Int32 playerCount)
        {
            /* PUTS DATA IN NEXT AVALIABLE SLOT
            playerNumbers[playerCount] = number;
            playerLastNames[playerCount] = lastName;
            playerPoints[playerCount] = points;
            playerCount++;
            */

            // PUTS DATA IN PLAYER ASECENDING ORDER
               Int32 insertIndex, shiftCount;
               insertIndex = GetInsertIndex(number, playerNumbers, playerCount);
               for (shiftCount = playerCount; shiftCount > insertIndex; shiftCount--)
               {
                   playerNumbers[shiftCount] = playerNumbers[shiftCount - 1];
                   playerLastNames[shiftCount] = playerLastNames[shiftCount - 1];
                   playerPoints[shiftCount] = playerPoints[shiftCount - 1];
               }
               playerNumbers[insertIndex] = number;
               playerLastNames[insertIndex] = lastName;
               playerPoints[insertIndex] = points;
               playerCount++;

        }
        //Returns the index of the first player number in the table that is greater
        //than the player number to be inserted
        static Int32 GetInsertIndex(Int32 playerNumber, Int32[] playerNumbers,
            Int32 playerCount)
        {
            Int32 index = 0;
            bool found = false;
            while (index < playerCount && found == false)
                if (playerNumbers[index] > playerNumber)
                    found = true;
                else
                    index++;
            return index;
        }

        //Returns the index of the player number in the table 
        //or -1 if the number is not found
        static Int32 GetPlayerIndex(Int32 playerNumber,
            Int32[] playerNumbers, Int32 playerCount)
        {
            Int32 index = 0;
            bool found = false;
            while (index < playerCount && found == false)
                if (playerNumbers[index] == playerNumber)
                    found = true;
                else
                    index++;
            if (found == false)
                index = -1;
            return index;
        }

        //Lists the players in the tables
        static void ProcessList(Int32[] playerNumbers, String[] playerLastNames,
            Int32[] playerPoints, Int32 playerCount)
        {

            if (playerCount > 0)
            {
                Console.WriteLine("\n{0,7}   {1,-25}{2,6}\n", "Number", "Last Name", "Points");
                for (Int32 player = 0; player < playerCount; player++)
                    Console.WriteLine("{0,7}   {1,-25}{2,6}", playerNumbers[player], playerLastNames[player], playerPoints[player]);
            }
            else
                Console.WriteLine("\nList Players: the roster is empty");
        }

        //Returns a positive integer
        static Int32 GetPositiveInteger(String prompt)
        {
            Int32 n;
            Console.WriteLine(prompt);
            n = Int32.Parse(Console.ReadLine());
            while (n < 0)
            {
                Console.WriteLine("\nError: enter positive value");
                Console.WriteLine(prompt);
                n = Int32.Parse(Console.ReadLine());
            }
            return n;
        }

        //Returns a non-empty string
        static String GetString(String prompt)
        {
            String returnString;
            Console.WriteLine(prompt);
            returnString = Console.ReadLine();
            while (returnString == "")
            {
                Console.WriteLine("\nError: must enter keyboard data");
                Console.WriteLine(prompt);
                returnString = Console.ReadLine();
            }
            return returnString;
        }
    }
}

1 个答案:

答案 0 :(得分:2)

您无法在C#数组中添加或删除值。数组具有固定大小。也就是说,您可以更改任何元素的值,并且可以将新数组(减号和元素或其他元素)重新分配给原始变量。

int[] IDs = new int[] { 1, 2, 3 };
IDs[2] = 55; // was 3

IDs = new [] { 1, 2, 4, 5, 6 };

您还可以查看可以插入,更新或删除的通用列表List<>()