數組以及如何更新，刪除和檢索條目

Question

嗨，我有一個任務，我必須創建一個程序，其中包含三個數組，其中一個爲人名，一個爲得分點，一個爲玩家號碼，現在我已經完成了所有的陣列和事情，但我很困惑，我將如何檢索條目，更新條目或刪除條目，到目前爲止我的工作選項是創建玩家，列隊員和退出另外兩個我不知道該怎麼做，一些正確的方向指導將真正幫助請和謝謝。

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; 
     } 
    } 
} 

Answer 1

您無法添加或刪除C＃數組中的值。數組的大小是固定的。也就是說，你可以改變任何元素的值，你可以重新分配一個新的數組（減號和元素或附加元素）到原始變量。

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

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

你也可以看看泛型列表List<>()可以插入，更新或已刪除。