运行此程序时，我得到以下输出：
Please enter the Social Security Number for taxpayer 0: 111111111
Please enter the gross income for taxpayer 0: 20000
Please enter the Social Security Number for taxpayer 1: 555555555
Please enter the gross income for taxpayer 1: 50000
Please enter the Social Security Number for taxpayer 2: 333333333
Please enter the gross income for taxpayer 2: 5464166
Please enter the Social Security Number for taxpayer 3: 222222222
Please enter the gross income for taxpayer 3: 645641
Please enter the Social Security Number for taxpayer 4: 444444444
Please enter the gross income for taxpayer 4: 29000
Taxpayer # 1 SSN: 111111111, Income is $20,000.00, Tax is $0.00
Taxpayer # 2 SSN: 555555555, Income is $50,000.00, Tax is $0.00
Taxpayer # 3 SSN: 333333333, Income is $5,464,166.00, Tax is $0.00
Taxpayer # 4 SSN: 222222222, Income is $645,641.00, Tax is $0.00
Taxpayer # 5 SSN: 444444444, Income is $29,000.00, Tax is $0.00
未处理的异常：System.InvalidOperationException：无法比较数组中的两个元素。---> System.ArgumentException: 至少一个对象必须实现 IComparable。
在 System.Collections.Comparer.Compare(Object a, Object b)
在 System.Collections.Generic.ObjectComparer`1.Compare(T x, T y)
在 System.Collections.Generic.ArraySortHelper`1.SwapIfGreaterWithItems(T[]键，IComparer`1 比较器，Int32 a，Int32 b)
在 System.Collections.Generic.ArraySortHelper`1.QuickSort(T[] 键，Int32 左，Int32 右，IComparer`1 比较器)
在 System.Collections.Generic.ArraySortHelper `1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 比较器)
--- 内部异常堆栈跟踪结束 ---
在 System.Collections.Generic.ArraySortHelper`1.Sort(T[] 键，Int32 索引，Int32 长度，IComparer`1 比较器)
在 System.Array.Sort[T](T[] 数组，Int32 索引，Int32 长度， IComparer`1 comparer) at System.Array.Sort[T](T[] array)
at Assignment5.Taxpayer.Main(String[] args) in Program.cs:line 150
注意应该是税额的行尾的 0 吗？？？
这是代码：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace taxes
{
class Rates
{
// Create a class named rates that has the following data members:
private int incLimit;
private double lowTaxRate;
private double highTaxRate;
// use read-only accessor
public int IncomeLimit
{ get { return incLimit; } }
public double LowTaxRate
{ get { return lowTaxRate; } }
public double HighTaxRate
{ get { return highTaxRate; } }
//A class constructor that assigns default values
public Rates()
{
int limit = 30000;
double lowRate = .15;
double highRate = .28;
incLimit = limit;
lowTaxRate = lowRate;
highTaxRate = highRate;
}
//A class constructor that takes three parameters to assign input values for limit, low rate and high rate.
public Rates(int limit, double lowRate, double highRate)
{
}
// A CalculateTax method that takes an income parameter and computes the tax as follows:
public int CalculateTax(int income)
{
int limit = 0;
double lowRate = 0;
double highRate = 0;
int taxOwed = 0;
// If income is less than the limit then return the tax as income times low rate.
if (income < limit)
taxOwed = Convert.ToInt32(income * lowRate);
// If income is greater than or equal to the limit then return the tax as income times high rate.
if (income >= limit)
taxOwed = Convert.ToInt32(income * highRate);
return taxOwed;
}
} //end class Rates
// Create a class named Taxpayer that has the following data members:
public class Taxpayer
{
//Use get and set accessors.
string SSN
{ get; set; }
int grossIncome
{ get; set; }
// Use read-only accessor.
public int taxOwed
{
get { return taxOwed; }
}
// The Taxpayer class should be set up so that its objects are comparable to each other based on tax owed.
class taxpayer : IComparable
{
public int taxOwed { get; set; }
public int income { get; set; }
int IComparable.CompareTo(Object o)
{
int returnVal;
taxpayer temp = (taxpayer)o;
if (this.taxOwed > temp.taxOwed)
returnVal = 1;
else
if (this.taxOwed < temp.taxOwed)
returnVal = -1;
else
returnVal = 0;
return returnVal;
} // End IComparable.CompareTo
} //end taxpayer IComparable class
// **The tax should be calculated whenever the income is set.
// The Taxpayer class should have a getRates class method that has the following.
public static void GetRates()
{
// Local method data members for income limit, low rate and high rate.
int incLimit = 0;
double lowRate;
double highRate;
string userInput;
// Prompt the user to enter a selection for either default settings or user input of settings.
Console.Write("Would you like the default values (D) or would you like to enter the values (E)?: ");
/* If the user selects default the default values you will instantiate a rates object using the default constructor
* and set the Taxpayer class data member for tax equal to the value returned from calling the rates object CalculateTax method.*/
userInput = Convert.ToString(Console.ReadLine());
if (userInput == "D" || userInput == "d")
{
Rates rates = new Rates();
rates.CalculateTax(incLimit);
} // end if
/* If the user selects to enter the rates data then prompt the user to enter values for income limit, low rate and high rate,
* instantiate a rates object using the three-argument constructor passing those three entries as the constructor arguments and
* set the Taxpayer class data member for tax equal to the valuereturned from calling the rates object CalculateTax method. */
if (userInput == "E" || userInput == "e")
{
Console.Write("Please enter the income limit: ");
incLimit = Convert.ToInt32(Console.ReadLine());
Console.Write("Please enter the low rate: ");
lowRate = Convert.ToDouble(Console.ReadLine());
Console.Write("Please enter the high rate: ");
highRate = Convert.ToDouble(Console.ReadLine());
Rates rates = new Rates(incLimit, lowRate, highRate);
rates.CalculateTax(incLimit);
}
}
static void Main(string[] args)
{
Taxpayer[] taxArray = new Taxpayer[5];
Rates taxRates = new Rates();
// Implement a for-loop that will prompt the user to enter the Social Security Number and gross income.
for (int x = 0; x < taxArray.Length; ++x)
{
taxArray[x] = new Taxpayer();
Console.Write("Please enter the Social Security Number for taxpayer {0}: ", x + 1);
taxArray[x].SSN = Console.ReadLine();
Console.Write("Please enter the gross income for taxpayer {0}: ", x + 1);
taxArray[x].grossIncome = Convert.ToInt32(Console.ReadLine());
}
Taxpayer.GetRates();
// Implement a for-loop that will display each object as formatted taxpayer SSN, income and calculated tax.
for (int i = 0; i < taxArray.Length; ++i)
{
Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome));
} // end for
// Implement a for-loop that will sort the five objects in order by the amount of tax owed
Array.Sort(taxArray);
Console.WriteLine("Sorted by tax owed");
for (int i = 0; i < taxArray.Length; ++i)
{
Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome));
}
} //end main
} // end Taxpayer class
} //end
关于为什么美元金额为 0 以及为什么排序不起作用的任何线索？