所以我之前已经问过这个问题，但似乎无法到达任何地方所以我想我会再问一次，也许有人可以帮助我现在已经让我的代码的另一部分工作了。所以我需要知道如何更新和删除条目。我想澄清一点，我想通过用户输入来做到这一点。
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 != 'R' //JG
&& menuItem != 'L' && menuItem != 'X' && menuItem != 'U')
{
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;
case 'R': //JG
ProcessRetrieve(playerNumbers, playerLastNames, playerPoints, ref playerCount, MAXPLAYERS);
break;
case 'U':
ProcessUpdate(playerNumbers, playerLastNames, playerPoints, playerCount, MAXPLAYERS);
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;
}
// retrieve single value from an array
//static void ProcessRetrieve(Int32[] playerNumbers, String[] playerLastNames
//, Int32[] playerPoints, Int32 playerCount)
//{
//}
所以在这里我开始检索一个有效的单个条目的过程，并且是一个可以通过修改以使用下两个函数来重用的函数。
static void ProcessRetrieve(Int32[] playerNumbers, String[] playerLastNames,
Int32[] playerPoints, ref Int32 playerCount, Int32 MAXPLAYERS)
{
int player;// Player number to find
int playerindex;//index of the player number in Array
if (playerCount < MAXPLAYERS)
{
player = GetPositiveInteger("\nRetrieve Player: please enter the player's number"); //JG I used the same mechanism when you are creating the record, when you create yu check if it exists
/** If it exists you say record exists in this case I said display the existing record**/
playerindex = GetPlayerIndex(player, playerNumbers, playerCount);
if (playerindex != -1)// !-1 means Does not exist JG
{
Console.WriteLine("{0,7} {1,-25}{2,6}", playerNumbers[playerindex], playerLastNames[playerindex], playerPoints[playerindex]);
Console.WriteLine();
}
else
Console.WriteLine("\nRetrieve Player: the player number does not exists");
}
else
Console.WriteLine("\nRetrieve Player: the player does not exist in the roster");
}
现在这里是我遇到困难的地方，我如何使这个代码更新而不是检索我绝对丢失在这里我已经看了很多文章，只发现如何通过代码更改数组而不是用户输入
static void ProcessUpdate(Int32[] playerNumbers,
string[] playerLastnames, Int32[] playerpoints, Int32 playerCounts, Int32 MAXPLAYERS)
{
int player;// Player number to find
int playerindex;//index of the player number in Array
if (playerCounts < MAXPLAYERS || playerCounts == MAXPLAYERS)
{
player = GetPositiveInteger("\nUpdate Player: please enter the player's number");
playerindex = GetPlayerIndex(player, playerNumbers, playerCounts);
if (playerindex != -1)
{
Console.WriteLine("{0,7} {1,-25}{2,6}", playerNumbers[playerindex], playerLastnames[playerindex], playerpoints[playerindex]);
Console.WriteLine();
}
else
Console.WriteLine("\nUpdate Player: the player number does not exists");
}
else
Console.WriteLine("\nUpdate Player: the player does not exist in the roster");
}
}
}
答案 0 :(得分：1)
在您的代码中，您已经拥有了创建更新功能所需的构建块。我们来看看它们是什么。
您必须先询问玩家编号。您已在ProcessUpdate方法中实现了此功能。
player = GetPositiveInteger("\nUpdate Player: please enter the player's number");
您必须找到与玩家编号匹配的数组索引。您已经在ProcessUpdate方法中实现了这一点。
playerindex = GetPlayerIndex(player, playerNumbers, playerCounts);
您需要询问用户新的播放器数据。您已经在ProcessCreate方法中实现了这一点 - 并且只需要更改字符串以澄清我们现在要求更新的数据。
lastName = GetString("\nUpdate Player: please enter the player's updated last name");
points = GetPositiveInteger("\nUpdate Player: please enter the player's updated points");
最后，您必须将刚从用户那里获得的数据放入数组中。您已经在InsertPlayer中实现了这一点 - 我们只需注意在这里使用正确的变量名称。
playerLastNames[playerindex] = lastName;
playerPoints[playerindex] = points;
将所有这些放在一起（包括变量声明和健全性检查），您的ProcessUpdate方法应如下所示：
static void ProcessUpdate(Int32[] playerNumbers,
string[] playerLastnames, Int32[] playerpoints, Int32 playerCounts, Int32 MAXPLAYERS)
{
int player;// Player number to find
int playerindex;//index of the player number in Array
String lastName;
int points;
if (playerCounts < MAXPLAYERS || playerCounts == MAXPLAYERS)
{
player = GetPositiveInteger("\nUpdate Player: please enter the player's number");
playerindex = GetPlayerIndex(player, playerNumbers, playerCounts);
if (playerindex != -1)
{
lastName = GetString("\nUpdate Player: please enter the player's updated last name");
points = GetPositiveInteger("\nUpdate Player: please enter the player's updated points");
playerLastNames[playerindex] = lastName;
playerPoints[playerindex] = points;
}
else
Console.WriteLine("\nUpdate Player: the player number does not exists");
}
else
Console.WriteLine("\nUpdate Player: the player does not exist in the roster");
}
}
一般来说，程序的结构不是如何正确执行的示例（抱歉）。但是，我不知道你的编程课程。您的课程是否已经涵盖了结构，对象（面向对象的编程）或其他“高级”数据类型（如字典），或者这些是未来的主题吗？我知道你需要使用3个数组，但是只有在struct的帮助下，你才能在满足要求的同时显着清理你的代码。
答案 1 :(得分：0)
下面我写了一个关于如何通过用户输入更新玩家得分和名称的示例。 通过保持每个玩家相同索引中的nums，names和points的索引，我们可以跟踪它们。
// Make sure the indexes of the arrays are aligned with the player array
// (to keep track which points are for which player)
int[] playerNums = new int[10];
string[] playerNames = new string[10];
int[] playerPoints = new int[10];
// We now add the user here (you do it somewhere from user input)
playerNums[0] = 1;
playerNames[0] = "Tim";
playerPoints[0] = 10;
char key = Console.ReadKey(true).KeyChar;
if (char.IsDigit(key))
{
// We get the number from the char.
int inputNum = int.Parse(key.ToString());
// We make sure the user isn't giving an index past the length of our arrays
// (which are 10 in size).
if (inputNum > -1 && inputNum < playerNums.Length - 1)
{
playerNames[inputNum] = "John"; // Tim now becomes John.
playerPoints[inputNum] += 5; // Increase John's score.
}
}
告诉我这是否是您正在寻找的答案。
答案 2 :(得分：0)
而不是数组使用如下的Dictionary，因此您不需要为所有数组维护任何索引，如果您想搜索特定元素，则非常容易。玩家号码是每个玩家信息的关键，你可以选择你想要的任何键。 请参阅以下链接了解更多详情 http://www.dotnetperls.com/dictionary
命名空间播放器 { 课程 {
static void Main(string[] args)
{
Dictionary<string, PlayerInfo> info = new Dictionary<string, PlayerInfo>();
for (int i = 0; i < 10; i++)
{
Console.WriteLine("Enter Player Number");
string playerNumber = Console.ReadLine();
info.Add(playerNumber, new PlayerInfo());
Console.WriteLine("Enter Player Name");
info[playerNumber].PlayerName = Console.ReadLine();
Console.WriteLine("Enter Player Points");
info[playerNumber].points = Console.ReadLine();
}
Console.WriteLine("Enter the player number to be deleted");
string playerNumberToDelete = Console.ReadLine();
info.Remove(playerNumberToDelete);
Console.WriteLine("Enter a player number to update");
string playerNumberToUpdate = Console.ReadLine();
Console.WriteLine("Enter Player Name");
info[playerNumberToUpdate].PlayerName = Console.ReadLine();
Console.WriteLine("Enter Player Points");
info[playerNumberToUpdate].points = Console.ReadLine();
Console.WriteLine("Enter player number dispaly deatils");
string playerNumberToDisplay = Console.ReadLine();
Console.WriteLine("Name " + info[playerNumberToDisplay].PlayerName);
Console.WriteLine("Points " + info[playerNumberToDisplay].points);
}
}
class PlayerInfo
{
public string PlayerName;
public string points;
}
}
答案 3 :(得分：0)
您的ProcessUpdate应如下所示
static void ProcessUpdate(Int32[] playerNumbers, string[] playerLastnames, Int32[] playerpoints, Int32 playerCounts, Int32 MAXPLAYERS)
{
int player;// Player number to find
int playerindex;//index of the player number in Array
if (playerCounts <= MAXPLAYERS)
{
player = GetPositiveInteger("\nUpdate Player: please enter the player's number");
playerindex = GetPlayerIndex(player, playerNumbers, playerCounts);
if (playerindex != -1)
{
string lastName = GetString("\nCreate Player: please enter the player's last name");
int points = GetPositiveInteger("\nCreate Player: please enter the player's points");
playerLastnames[playerindex] = lastName;
playerpoints[playerindex] = points;
Console.WriteLine("{0,7} {1,-25}{2,6}", playerNumbers[playerindex], playerLastnames[playerindex], playerpoints[playerindex]);
Console.WriteLine();
}
else
Console.WriteLine("\nUpdate Player: the player number does not exists");
}
else
Console.WriteLine("\nUpdate Player: the player does not exist in the roster");
}