如何在 c# winform 應用程序中使用來自另一個 class 的字符串？

Question

所以我在 Visual Studio C# 中編寫了一個 winform 應用程序，它使用生成的密鑰鎖定用戶類型的消息。 用戶需要知道密鑰的創建日期，該日期是從用戶鍵入“textBox1”時程序生成的文件中收集的。 我正在做的是使用字符串來驗證“password.txt”文件的創建日期，如果不是用戶輸入的日期，則消息將不會打開。 問題雖然我在使用 static 屬性時遇到問題，但此錯誤：

錯誤 CS0120 非靜態字段、方法或屬性“Encryptor1.Encrypt(string)”UniveralWindowsTextPGP C:\Users\keife\source\repos\UniveralWindowsTextPGP\Univeral\UniveralWindowsTextPGP\UniveralWindowsTextPGP 需要 object 引用

這是我實現加密和解密方法的地方：

namespace UniveralWindowsTextPGP
{
    class Encryptor1

    {
        public static string IV = "1a1a1a1a1a1a1a1a";
        public static string Key = "1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a13";

        public static string Encrypt(string decrypted)
        {
            byte[] textbytes = ASCIIEncoding.ASCII.GetBytes(decrypted);
            AesCryptoServiceProvider endec = new AesCryptoServiceProvider();
            endec.BlockSize = 128;
            endec.KeySize = 256;
            endec.IV = ASCIIEncoding.ASCII.GetBytes(IV);
            endec.Key = ASCIIEncoding.ASCII.GetBytes(Key);
            endec.Padding = PaddingMode.PKCS7;
            endec.Mode = CipherMode.CBC;
            ICryptoTransform icrypt = endec.CreateEncryptor(endec.Key, endec.IV);
            byte[] enc = icrypt.TransformFinalBlock(textbytes, 0, textbytes.Length);
            icrypt.Dispose();
            return Convert.ToBase64String(enc);
        }

        public static string Decrypted(string encrypted)
        {
            DateTime creation = File.GetCreationTime(@"C:\password.txt");

            FileInfo fi = new FileInfo(@"C:\password.txt");
             var created = fi.CreationTime;
            if (fi.CreationTime != Form2.keyhere)

// 上面一行是這部分發生錯誤的地方。

{
                string message = "That is incorrect, access is denied.";
                MessageBox.Show(message);
            }
            else

            { 
                    byte[] textbytes = Convert.FromBase64String(encrypted);
                    AesCryptoServiceProvider endec = new AesCryptoServiceProvider();
                    endec.BlockSize = 128;
                    endec.KeySize = 256;
                    endec.IV = ASCIIEncoding.ASCII.GetBytes(IV);
                    endec.Key = ASCIIEncoding.ASCII.GetBytes(Key);
                    endec.Padding = PaddingMode.PKCS7;
                    endec.Mode = CipherMode.CBC;
                    ICryptoTransform icrypt = endec.CreateDecryptor(endec.Key, endec.IV);
                    byte[] enc = icrypt.TransformFinalBlock(textbytes, 0, textbytes.Length);
                    icrypt.Dispose();
                    return System.Text.ASCIIEncoding.ASCII.GetString(enc);
                }
            
        }
    } }

// 這里是表格：

  namespace UniveralWindowsTextPGP

{
public partial class Form2 : Form
{
    public Form2()
    {
        InitializeComponent();
    }

    private void label1_Click(object sender, EventArgs e)
    {

    }

    private void Form2_Load(object sender, EventArgs e)
    {

    }

    private void richTextBox1_TextChanged(object sender, EventArgs e)
    {

    }

    private void label2_Click(object sender, EventArgs e)
    {

    }

    private void button1_Click(object sender, EventArgs e)
    {

    }

    private void passwordbox_TextChanged(object sender, EventArgs e)
    {

    }

    private void richTextBox1_TextChanged_1(object sender, EventArgs e)
    {

    }

    private void Decrypt_Click(object sender, EventArgs e)
    {
        string dir = richTextBox1.Text;

        StreamReader sr = new StreamReader("encryptedmessagehere.txt");
        string line = sr.ReadLine();

        richTextBox1.Text = Encryptor1.Decrypted(Convert.ToString(line));
    }

    private void Form2_Load_1(object sender, EventArgs e)
    {

    }

    private void label3_Click(object sender, EventArgs e)
    {

    }

    private void button1_Click_1(object sender, EventArgs e)
    {
        string dir = richTextBox2.Text;




        string enctxt = Encryptor1.Encrypt(richTextBox2.Text);
        System.IO.File.WriteAllText(@"C:\encryptedmessagehere.txt", enctxt);

    }

    private void label4_Click(object sender, EventArgs e)
    {

    }

    private void richTextBox2_TextChanged(object sender, EventArgs e)
    {
        richTextBox2.EnableContextMenu();
    }

    private void button2_Click(object sender, EventArgs e)
    {
        string dir = richTextBox2.Text;

        StreamReader sr = new StreamReader(@"C:\encryptedmessagehere.txt");
        string line = sr.ReadLine();

        richTextBox2.Text = Encryptor1.Decrypted(Convert.ToString(line));
        System.IO.File.WriteAllText(@"C:\decryptedmessagehere.txt", line);
       
    }

    private void button3_Click(object sender, EventArgs e)
    {
        Form3 f3 = new Form3();
        f3.Show();

    }

    private void button4_Click(object sender, EventArgs e)
    {
        Form f4 = new Form4();
        f4.Show();

    }

    public void passwordbox1_TextChanged(object sender, EventArgs e)
    {
       

    }

    private void richTextBox3_TextChanged(object sender, EventArgs e)
    {
        string richTextBox3 = "";
    }

    public void textBox1_TextChanged(object sender, EventArgs e)
    {
        
        TextWriter txt = new StreamWriter("C:/password.txt");
        txt.Write(textBox1.Text);
        txt.Close();
        public string keyhere = textBox1.Text;

// 這是這里發生錯誤的地方。

非常感謝，感謝您的想法。

Answer 1

1. 您不能在方法中聲明 class 變量。

這一行在這里：

public string keyhere = textBox1.Text;

在textBox1_TextChanged方法中。

2. 您在此行中使用訪問 static 變量的語法：

   if (fi.CreationTime.= Form2.keyhere)

沒有 static 變量Form2.keyhere 。 這就是編譯器抱怨的原因。

您可以通過創建一個來解決這兩個問題：

public static string keyhere

public void textBox1_TextChanged(object sender, EventArgs e)
{
    
    TextWriter txt = new StreamWriter("C:/password.txt");
    txt.Write(textBox1.Text);

    keyhere = textBox1.Text;

    txt.Close(); // write this as last call, otherwise textBox1 might already be disposed when you try to access textBox1.Text;
}

免責聲明：這是一個臨時解決方案，它違反了干凈編碼的某些規則。 特別是單一責任原則。 最好將所有必要的信息傳遞給Decrypted方法並在那里使用它。 class Encryptor1不應該知道有關Form或其他 UI 元素的任何信息。