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我目前正在使用C＃开发员工数据库。我有4个不同的类组成我的数据库;受薪雇员，每小时雇员，佣金雇员和基本工资雇员。我有一个名为“employee”的基类，它包含每个员工类型的名字，姓氏和SSN。如何从数据库（C＃）中的数组中删除数据？
目前，我可以在运行代码时单独打印每位员工。我使用测试输入文件来测试文件中的员工类型。它在输出文件中输出它的相应类型的员工。
现在，我可以创建员工记录，我也希望能够从数组中删除员工记录。
我对这个方法被称为
private void DeleteEmployeeRecord()
{
Console.WriteLine("***** DeleteEmployeeRecord");
}
我有开始使用此方法的麻烦。关于如何从阵列中删除员工的任何提示或想法？
下面是员工数据库的代码，其中为系统执行所有操作，例如为员工创建记录，查找员工记录，删除员工记录等。正如我所提到的，我只有Create方法工作，而不是其余。我会很高兴地感谢我能够理解如何从我的临时阵列中删除一名员工。
**EmployeeDB:**
using System;
using System.IO;
namespace PayrollDB
{
internal class EmployeeDB
{
public const string SALARIED = "SALARIED";
public const string BASEPLUS = "BASEPLUS";
public const string COMMISSION = "COMMISSION";
public const string HOURLY = "HOURLY";
public const char CREATE_C = 'C';
public const char CREATE_c = 'c';
public const char SALARIED_S = 'S';
public const char SALARIED_s = 's';
public const char BASEPLUS_B = 'B';
public const char BASEPLUS_b = 'b';
public const char COMMISSION_M = 'M';
public const char COMMISSION_m = 'm';
public const char HOURLY_H = 'H';
public const char HOURLY_h = 'h';
// storage for all the students during the database operations
private Employee[] employees;
public EmployeeDB()
{
}
internal void ReadDataFromInputFile()
{
// create and intialize the file objects
FileStream fstream = new FileStream("INPUT.txt", FileMode.Open, FileAccess.Read);
StreamReader infile = new StreamReader(fstream); // FileStream
int numberOfRecords = int.Parse(infile.ReadLine());
employees = new Employee[numberOfRecords];
for (int i = 0; i < employees.Length; i++)
{
string employeeType = infile.ReadLine();
// read in data for an employee
string firstName = infile.ReadLine();
string lastName = infile.ReadLine();
string socialSecurityNumber = infile.ReadLine();
// how many more things are there to read?
if(employeeType == SALARIED)
{
decimal weeklySalary = decimal.Parse(infile.ReadLine());
// make a employee using the data you just read
// put the employee into the array
employees[i] = new Salaried(firstName, lastName, socialSecurityNumber, weeklySalary);
}
else if(employeeType == BASEPLUS)
{
decimal grossSales = decimal.Parse(infile.ReadLine());
decimal commissionRate = decimal.Parse(infile.ReadLine());
decimal baseSalary = decimal.Parse(infile.ReadLine());
// make an employee using the data you just read
// put the employee into the array
employees[i] = new BasePlus(firstName, lastName, socialSecurityNumber, grossSales, commissionRate, baseSalary);
}
else if (employeeType == COMMISSION)
{
decimal grossSales = decimal.Parse(infile.ReadLine());
decimal commissionRate = decimal.Parse(infile.ReadLine());
// make a student using the data you just read
// put the student into the array
employees[i] = new Commission(firstName, lastName, socialSecurityNumber, grossSales, commissionRate);
}
else if (employeeType == HOURLY)
{
decimal hourlyWage = decimal.Parse(infile.ReadLine());
decimal hoursWorked = decimal.Parse(infile.ReadLine());
// make a student using the data you just read
// put the student into the array
employees[i] = new Hourly(firstName, lastName, socialSecurityNumber, hourlyWage, hoursWorked);
}
else
{
Console.WriteLine("ERROR: That is not a valid employee type.");
}
}
// close the file or release the resource
infile.Close();
}
internal void WriteDataToOutputFile()
{
// create and open an output file
FileStream fstream = new FileStream("OUTPUT.txt", FileMode.Create, FileAccess.Write);
StreamWriter outfile = new StreamWriter(fstream);
// write the size of the array
outfile.WriteLine(employees.Length);
// write the data from the objects in the array to the output file
foreach (var employee in employees)
{
if (employee is Hourly)
{
var hourly = (Hourly)employee;
outfile.Write(hourly.ToDataFileString());
}
else if (employee is Salaried)
{
var salaried = (Salaried)employee;
outfile.Write(salaried.ToDataFileString());
}
else if (employee is Commission)
{
var commission = (Commission)employee;
outfile.Write(commission.ToDataFileString());
}
else if (employee is BasePlus)
{
var baseplus = (BasePlus)employee;
outfile.Write(baseplus.ToDataFileString());
}
}
// close the output file
outfile.Close();
}
public void PrintAllRecords()
{
Console.WriteLine("** Contents of db ***************");
foreach (var emp in employees)
{
Console.WriteLine(emp);
}
}
// main method that operates the application once we get
// all the data read into it
internal void OperateDatabase()
{
// explain the program to the user
DisplayProgramExplanation();
ConsoleKeyInfo choice;
do
{
// user interface
PresentUserInterface();
//string choice = Console.ReadLine();
//selection = choice[0];
choice = Console.ReadKey();
switch(choice.KeyChar)
{
case CREATE_C:
case CREATE_c:
CreateEmployeeRecord();
break;
case 'F':
case 'f':
FindAndPrintEmployeeRecord();
break;
case 'U':
case 'u':
UpdateEmployeeRecord();
break;
case 'D':
case 'd':
DeleteEmployeeRecord();
break;
case 'P':
case 'p':
PrintAllEmployeeRecords();
break;
default:
break;
}
} while ((choice.KeyChar != 'Q') && (choice.KeyChar != 'q'));
}
private void FindAndPrintEmployeeRecord()
{
throw new NotImplementedException();
}
private void PrintAllEmployeeRecords()
{
Console.WriteLine("***** PrintAllEmployeeRecords");
}
private void DeleteEmployeeRecord()
{
Console.WriteLine("***** DeleteEmployeeRecord");
}
private void UpdateEmployeeRecord()
{
Console.WriteLine("***** UpdateEmployeeRecord");
}
// Find a student object in the array.
// Inputs: email - a string containing the email address of
// the student that is being searched for
// Output: the student object with a matching email, otherwise null ref
private Employee FindEmployeeRecord(string socialSecurityNumber)
{
// look through the collection at each employee
foreach (var emp in employees)
{
// if we find a student with matching social security number
if(emp.SocialSecurityNumber == socialSecurityNumber)
{
// return the object
return emp;
}
}
// if we get through the entire collection with no student
// object find that matches the search email,
// so return a null reference
return null;
}
private void CreateEmployeeRecord()
{
Console.WriteLine(" :: CreateStudentRecord");
//display prompt that asks for employee's social security number
Console.Write("Enter the social security number for the record to add: ");
//user types in the student email
string socialSecurityNumber = Console.ReadLine();
// check to see if record already exists in the database
// if it does, return back to main menu, issue a message
Employee emp = FindEmployeeRecord(socialSecurityNumber);
if(emp != null)
{
Console.WriteLine("Error: " + socialSecurityNumber + " is already in the database.");
return;
}
//display prompt that asks for type of student
Console.Write("Enter the type of employee: ");
ConsoleKeyInfo employeeType = Console.ReadKey();
//display prompt that asks for first name
Console.Write("Enter the first name: ");
string firstName = Console.ReadLine();
//display prompt that asks for last name
Console.Write("Enter the last name: ");
string lastName = Console.ReadLine();
// if type of student was U
if(employeeType.KeyChar == SALARIED_S || employeeType.KeyChar == SALARIED_s)
{
//display prompts for the weekly salary
Console.Write("Enter the weekly salary: ");
decimal weeklySalary = decimal.Parse(Console.ReadLine());
// make an undergrad student
emp = new Salaried(firstName, lastName, socialSecurityNumber, weeklySalary);
}
else if (employeeType.KeyChar == BASEPLUS_B || employeeType.KeyChar == BASEPLUS_b)
{
//if student type is BasePlus Employee prompt for base salary
Console.Write("Enter the Base Salary: ");
decimal baseSalary = decimal.Parse(Console.ReadLine());
// prompt for the Gross Sales
Console.Write("Enter the Gross Sales: ");
decimal grossSales = decimal.Parse(Console.ReadLine());
//prompt for the Commission Rate
Console.Write("Enter the Commission Rate: ");
decimal commissionRate = decimal.Parse(Console.ReadLine());
// make a grad student
emp = new BasePlus(firstName, lastName, socialSecurityNumber, grossSales, commissionRate, baseSalary);
}
else if (employeeType.KeyChar == COMMISSION_M || employeeType.KeyChar == COMMISSION_m)
{
// prompt for the Gross Sales
Console.Write("Enter the Gross Sales: ");
decimal grossSales = decimal.Parse(Console.ReadLine());
//prompt for the Commission Rate
Console.Write("Enter the Commission Rate: ");
decimal commissionRate = decimal.Parse(Console.ReadLine());
// make a grad student
emp = new Commission(firstName, lastName, socialSecurityNumber, grossSales, commissionRate);
}
else if (employeeType.KeyChar == HOURLY_H || employeeType.KeyChar == HOURLY_h)
{
//if student type is BasePlus Employee prompt for base salary
Console.Write("Enter the Hourly Wage: ");
decimal hourlyWage = decimal.Parse(Console.ReadLine());
// prompt for the Gross Sales
Console.Write("Enter the Hours Worked: ");
decimal hoursWorked = decimal.Parse(Console.ReadLine());
// make a grad student
emp = new Hourly(firstName, lastName, socialSecurityNumber, hourlyWage, hoursWorked);
}
else
{
Console.WriteLine(employeeType.KeyChar + " is not a type of employee.");
return;
}
//display the current student data and ask for confirm
// ask user to confirm
// the db saves the record, and returns to main menu - steps:
// and insert the newly created student object into the array
// 1 - make an array that is 1 "bigger" than students
Employee[] biggerEmployeeArray = new Employee[employees.Length + 1];
// 2 - copy all objects from students to the bigger array
// (at the same index val)
for (int i = 0; i < employees.Length; i++)
{
biggerEmployeeArray[i] = employees[i];
}
// put stu in the last slot in the bigger array
biggerEmployeeArray[biggerEmployeeArray.Length - 1] = emp;
// make the students ref point to the bigger array
employees = biggerEmployeeArray;
}
private void PresentUserInterface()
{
Console.WriteLine(@"
Select from the following options:
[C]reate (a new employee)
[F]ind (search for a record)
[U]pdate
[D]elete
[P]rint all records in the database
[Q]uit
");
}
private void DisplayProgramExplanation()
{
Console.WriteLine(@"
********************************************
Welcome to the Employee Database application.
You can execute most typical db commnds,
including
[C]reate, [R]ead [U]pdate, and [D]elete
for the employee records that are present.
");
}
}
}
这是一个很大的代码，所以我没有把它都在这里，我所展示的权利，现在正好是类“员工DB”中“创造”的方法。我认为如果我在这里发布全部内容会更有意义。 –