谢谢大家帮我解决问题，不过我没有分了啊，不要见怪~！

Question

public static void Main()
{
string str;
Console.WriteLine("Please enter a number:");
str=Console.ReadLine();
if(str=="1")
  Console.WriteLine(date.Monday);
Console.WriteLine(str);
}

Answer 1

 一个控制台小程序：using System;class name
{
enum date
{
Monday=1,
Tuesday=2,
Wednesday=3
} public static void Main()
{
while (true) 
{
string str;
Console.WriteLine("Please enter a date:");
str=Console.ReadLine();
switch(str) 
{
case "Monday":
Console.WriteLine("The date is:{0}",(int)date.Monday);
break;
case "Tuesday":
Console.WriteLine("The date is:{0}",(int)date.Tuesday);
break;
case "Wednesday":
Console.WriteLine("The date is:{0}",(int)date.Wednesday);
break;
default: 
Console.WriteLine("Object is unknown.");
break;
}
}
}
} :)