我基本上已经编写了整个程序，但我正在努力使其更清晰。在选项为 1、2、3 或 4 的动物选择菜单上，如果选择了另一个选项，我希望它立即返回错误。目前，如果选择了 5，系统会提示用户先输入一个名称，然后再返回一个有效选择的错误。我已经尝试自己重新排列代码，但最终还是无法正常工作或出现错误。非常感谢任何建议或帮助。
using System;
abstract class Animal
{
public string Name { get; set; }
public abstract void Speak();
}
class Dog : Animal
{
public override void Speak()
{
Console.WriteLine($"The dog {Name} barks.");
}
}
class Cat : Animal
{
public override void Speak()
{
Console.WriteLine($"The cat {Name} meows.");
}
}
class Pig : Animal
{
public override void Speak()
{
Console.WriteLine($"The pig {Name} oinks.");
}
}
class Cow : Animal
{
public override void Speak()
{
Console.WriteLine($"The cow {Name} moos.");
}
}
class Program
{
static void Main(string[] args)
{
Animal[] animals = new Animal[100];
int animalCount = 0;
var menuChoice = "";
while (menuChoice != "3")
{
Console.WriteLine("Select an option:");
Console.WriteLine("1. Enter an animal");
Console.WriteLine("2. Have all animals speak");
Console.WriteLine("3. Exit");
menuChoice = Console.ReadLine();
switch (menuChoice)
{
case "1":
if (animalCount >= 100)
{
Console.WriteLine("Maximum number of animals reached.");
break;
}
Console.WriteLine("Select an animal:");
Console.WriteLine("1. Dog");
Console.WriteLine("2. Cat");
Console.WriteLine("3. Pig");
Console.WriteLine("4. Cow");
var animalChoice = Console.ReadLine();
Console.WriteLine("Enter the desired animal's name:");
var animalName = Console.ReadLine();
Animal animal = null;
switch (animalChoice)
{
case "1":
animals[animalCount] = new Dog { Name = animalName };
animalCount++;
Console.WriteLine($"Added a dog named {animalName}.");
break;
case "2":
animals[animalCount] = new Cat { Name = animalName };
animalCount++;
Console.WriteLine($"Added a cat named {animalName}.");
break;
case "3":
animals[animalCount] = new Pig { Name = animalName };
animalCount++;
Console.WriteLine($"Added a pig named {animalName}.");
break;
case "4":
animals[animalCount] = new Cow { Name = animalName };
animalCount++;
Console.WriteLine($"Added a cow named {animalName}.");
break;
default:
Console.WriteLine("That was not a valid animal selection, please choose again from the menu above.");
continue;
}
if (animal != null)
{
animals[animalCount] = animal;
animalCount++;
}
break;
case "2":
if (animalCount == 0)
{
Console.WriteLine("There are currently no assigned animals that can speak.");
}
else
{
for (int i = 0; i < animalCount; i++)
{
animals[i].Speak();
}
}
break;
case "3":
Console.WriteLine("Thank you for using Animal Farm");
break;
default:
Console.WriteLine("Invalid selection, please choose an option from the menu above.");
break;
}
}
}
}
}
我尝试重新排列代码以及通过谷歌搜索错误。
复制了你的代码。首先，你有一个额外的右大括号。其次，jdweng 已经给出了应该做什么的说明。实施这可能没什么大不了的，但希望这会有所帮助。
namespace ConsoleApp1 // note: actual namespace depends on the project name
{
abstract class Animal
{
public string Name { get; set; }
public abstract void Speak();
}
class Dog : Animal
{
public override void Speak()
{
Console.WriteLine($"The dog {Name} barks.");
}
}
class Cat : Animal
{
public override void Speak()
{
Console.WriteLine($"The cat {Name} meows.");
}
}
class Pig : Animal
{
public override void Speak()
{
Console.WriteLine($"The pig {Name} oinks.");
}
}
class Cow : Animal
{
public override void Speak()
{
Console.WriteLine($"The cow {Name} moos.");
}
}
class Program
{
static void Main(string[] args)
{
Animal[] animals = new Animal[100];
int animalCount = 0;
var menuChoice = "";
while (menuChoice != "3")
{
Console.WriteLine("Select an option:");
Console.WriteLine("1. Enter an animal");
Console.WriteLine("2. Have all animals speak");
Console.WriteLine("3. Exit");
menuChoice = Console.ReadLine();
switch (menuChoice)
{
case "1":
if (animalCount >= 100)
{
Console.WriteLine("Maximum number of animals reached.");
break;
}
// enter animals name before its type
Console.WriteLine("Enter the desired animal's name:");
var animalName = Console.ReadLine();
// add bool variable which tells if animals type was valid, false by default
var validEntry = false;
Animal animal = null;
// while loop where you keep entering animals type until it was valid. When valid type is entered, validEntry becomes true and while loop is finished
while (!validEntry)
{
Console.WriteLine("Select an animal:");
Console.WriteLine("1. Dog");
Console.WriteLine("2. Cat");
Console.WriteLine("3. Pig");
Console.WriteLine("4. Cow");
var animalChoice = Console.ReadLine();
switch (animalChoice)
{
case "1":
animals[animalCount] = new Dog { Name = animalName };
animalCount++;
Console.WriteLine($"Added a dog named {animalName}.");
// thats where you need assign true to validEntry
validEntry = true;
break;
case "2":
animals[animalCount] = new Cat { Name = animalName };
animalCount++;
Console.WriteLine($"Added a cat named {animalName}.");
validEntry = true;
break;
case "3":
animals[animalCount] = new Pig { Name = animalName };
animalCount++;
Console.WriteLine($"Added a pig named {animalName}.");
validEntry = true;
break;
case "4":
animals[animalCount] = new Cow { Name = animalName };
animalCount++;
Console.WriteLine($"Added a cow named {animalName}.");
validEntry = true;
break;
// if entry is invalid just print the error message and continue the while loop
default:
Console.WriteLine("That was not a valid animal selection, please choose again from the menu above.");
continue;
}
}
if (animal != null)
{
animals[animalCount] = animal;
animalCount++;
}
break;
case "2":
if (animalCount == 0)
{
Console.WriteLine("There are currently no assigned animals that can speak.");
}
else
{
for (int i = 0; i < animalCount; i++)
{
animals[i].Speak();
}
}
break;
case "3":
Console.WriteLine("Thank you for using Animal Farm");
break;
default:
Console.WriteLine("Invalid selection, please choose an option from the menu above.");
break;
}
}
}
}
}