C＃ - 当前上下文中不存在该名称

Question

I started my C# study this week and got trouble with this assignment.
The expensive book they made us buy does a poor job explaining this.
We have to use, If, Else, While and Do in this assignment.

I get this error, The name 'answer' does not exist in the current context.
What am I doing wrong?

int question = 25;

do
{
    Console.Write("Guess the number: ");
    string strAnswer = Console.ReadLine();
    int answer = Convert.ToInt32(strAnswer);

    if (answer < question)
    {
        Console.WriteLine("Too low, guess again. ");
    }
    else if (answer > question)
    {
        Console.WriteLine("Too high, guess again. ");
    }
}

while (answer != question);
Console.Write("Correct!");

Answer 1

Try this, answer defined in different scope, you need define it at higher scope,

 int question = 25;
 int answer = 0;
 do
 {
     Console.Write("Guess the number: ");
     string strAnswer = Console.ReadLine();
     answer = Convert.ToInt32(strAnswer);

     if (answer < question)
     {
         Console.WriteLine("Too low, guess again. ");
     }
     else if (answer > question)
     {
         Console.WriteLine("Too high, guess again. ");
     }
  }

  while (answer != question);
     Console.Write("Correct!");

Answer 2

answer is declared inside the scope of the do block. It will not be accessible outside ofthat block (in the while condition). Try:

int question = 25;
int answer;

do
{
   Console.Write("Guess the number: ");
   string strAnswer = Console.ReadLine();
   answer = Convert.ToInt32(strAnswer);

   if (answer < question)
   {
       Console.WriteLine("Too low, guess again. ");
   }
   else if (answer > question)
   {
       Console.WriteLine("Too high, guess again. ");
   }
}
while (answer != question);

Answer 3

Your answer variable is out of scope. Your declaring answer inside the DO braces, but trying to access it outside in your while loop