Question

我的代码

static int IntCheck(string num)
{
    int value;
    if (!int.TryParse(num, out value))
    {
        Console.WriteLine("I am sorry, I thought I said integer, let me check...");
        Console.WriteLine("Checking...");
        System.Threading.Thread.Sleep(3000);
        Console.WriteLine("Yup, I did, please try that again, this time with an integer");
        int NewValue = IntCheck(Console.ReadLine());
    }
    else
    {
        int NewValue = value;
    }
    return NewValue;
 }

错误

名称＆＃39; NewValue＆＃39;在当前上下文中不存在（第33行）

Answer 1

您需要在

之外声明

static int IntCheck(string num)
{
    int value;
    int NewValue;
    if (!int.TryParse(num, out value))
    {
        Console.WriteLine("I am sorry, I thought I said integer, let me check...");
        Console.WriteLine("Checking...");
        System.Threading.Thread.Sleep(3000);
        Console.WriteLine("Yup, I did, please try that again, this time with an integer");
        NewValue = IntCheck(Console.ReadLine());
    }
    else
    {
        NewValue = value;
    }
    return NewValue;
 }

Answer 2

NewValue的范围是if和else块。您需要在块外移动声明。

static int IntCheck(string num)
{
    int value;
    int NewValue;
    if (!int.TryParse(num, out value))
    {
        Console.WriteLine("I am sorry, I thought I said integer, let me check...");
        Console.WriteLine("Checking...");
        System.Threading.Thread.Sleep(3000);
        Console.WriteLine("Yup, I did, please try that again, this time with an integer");
        NewValue = IntCheck(Console.ReadLine());
    }
    else
    {
        NewValue = value;
    }
    return NewValue;
 }

即使声明，名称也不存在

2 个答案: