如果我理解正确，你试图使退格删除屏幕上可见的*字符和缓存字符在你的传递变量?

如果是这样，那么只需将你的else块更改为:

            else
            {
                Console.Write("\b");
                pass = pass.Remove(pass.Length -1);
            }

我的忽略控制字符和处理行换行:

public static string ReadLineMasked(char mask = '*')
{
    var sb = new StringBuilder();
    ConsoleKeyInfo keyInfo;
    while ((keyInfo = Console.ReadKey(true)).Key != ConsoleKey.Enter)
    {
        if (!char.IsControl(keyInfo.KeyChar))
        {
            sb.Append(keyInfo.KeyChar);
            Console.Write(mask);
        }
        else if (keyInfo.Key == ConsoleKey.Backspace && sb.Length > 0)
        {
            sb.Remove(sb.Length - 1, 1);

            if (Console.CursorLeft == 0)
            {
                Console.SetCursorPosition(Console.BufferWidth - 1, Console.CursorTop - 1);
                Console.Write(' ');
                Console.SetCursorPosition(Console.BufferWidth - 1, Console.CursorTop - 1);
            }
            else Console.Write("\b \b");
        }
    }
    Console.WriteLine();
    return sb.ToString();
}

下面是一个版本，增加了对Escape键的支持(它返回一个空字符串)

public static string ReadPassword()
{
    string password = "";
    while (true)
    {
        ConsoleKeyInfo key = Console.ReadKey(true);
        switch (key.Key)
        {
            case ConsoleKey.Escape:
                return null;
            case ConsoleKey.Enter:
                return password;
            case ConsoleKey.Backspace:
                if (password.Length > 0) 
                {
                    password = password.Substring(0, (password.Length - 1));
                    Console.Write("\b \b");
                }
                break;
            default:
                password += key.KeyChar;
                Console.Write("*");
                break;
        }
    }
}

我只是改进代码从问我简单，只是工作

    string pass = ""; //create empty password string
    Console.Write("Enter your password: ");
    ConsoleKeyInfo key;
    int passLen = 0; // base password length

    do
    {
        key = Console.ReadKey(true); //reading keyboard key

        if (key.Key == ConsoleKey.Escape) Environment.Exit(0); // If key is escape console will close (optional)

        if (key.Key != ConsoleKey.Backspace && key.Key != ConsoleKey.Enter) // on key with is not bacspase and enter 
        {
            pass += key.KeyChar; //password string add key value
            Console.Write("*"); // and print star as masked char 
            passLen++; // upgrading password length
        }
        else if (passLen > 0 && key.Key == ConsoleKey.Backspace) //if password have a any symbol and u press Backspace
        {   
                Console.Write("\b \b"); //Backspace delete star symbol and coursor back in line 
                passLen--; // password length is one less
                pass = pass[0..^1]; // new string passowrd is string without last charter 
        }
    } 
    while (key.Key != ConsoleKey.Enter); // if you press enter this stop execute with your password

    Console.WriteLine();
    Console.WriteLine("The Password You entered is : " + pass);

控制台。写(“b \ b \”);将从屏幕上删除星号字符，但在else块中没有任何代码可以从传递字符串变量中删除先前输入的字符。

这里是相关的工作代码，应该做你需要的:

var pass = string.Empty;
ConsoleKey key;
do
{
    var keyInfo = Console.ReadKey(intercept: true);
    key = keyInfo.Key;

    if (key == ConsoleKey.Backspace && pass.Length > 0)
    {
        Console.Write("\b \b");
        pass = pass[0..^1];
    }
    else if (!char.IsControl(keyInfo.KeyChar))
    {
        Console.Write("*");
        pass += keyInfo.KeyChar;
    }
} while (key != ConsoleKey.Enter);

这将用一个红色方块掩盖密码，然后在输入密码后恢复到原来的颜色。

它不会阻止用户使用复制/粘贴来获取密码，但如果它只是为了阻止别人从你的身后看，这是一个很好的快速解决方案。

Console.Write("Password ");
ConsoleColor origBG = Console.BackgroundColor; // Store original values
ConsoleColor origFG = Console.ForegroundColor;

Console.BackgroundColor = ConsoleColor.Red; // Set the block colour (could be anything)
Console.ForegroundColor = ConsoleColor.Red;

string Password = Console.ReadLine(); // read the password

Console.BackgroundColor= origBG; // revert back to original
Console.ForegroundColor= origFG;