使用asp.net在邮件链接中发送表单URL

Question

I have a requirement where I want to send the User the link of the form via Email . The link for every user will be different. Currently I am just passing hardcode value in the mail.

Here is my code.

sb.AppendLine("Please click on the link to view the details.");
            sb.AppendLine("</br></br>");
            sb.AppendLine("<a href='" + ConfigurationManager.AppSettings["ClickHereLink"].ToString() + "' >Click here to open request</a>. ");
            sb.AppendLine("</br></br>");
            sb.AppendLine("<b>This is a system generated mail. Please do not reply to the sender.</b>");

And the ClickHereLink is been defined in Web.config like below

<add key="ClickHereLink" value="https://www.test.com"/>

How can I send dynamic link for every user based on the details

Encryption Method

public static class EncryptDecrypt
{
    public static string Encrypt(string clearText)
    {
        string EncryptionKey = "MAKV2SPBNI99212";
        byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
        using (Aes encryptor = Aes.Create())
        {
            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(clearBytes, 0, clearBytes.Length);
                    cs.Close();
                }
                clearText = Convert.ToBase64String(ms.ToArray());
            }
        }
        return clearText;
    }
    public static string Decrypt(string cipherText)
    {
        string EncryptionKey = "MAKV2SPBNI99212";
        cipherText = cipherText.Replace(" ", "+");
        byte[] cipherBytes = Convert.FromBase64String(cipherText);
        using (Aes encryptor = Aes.Create())
        {
            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(cipherBytes, 0, cipherBytes.Length);
                    cs.Close();
                }
                cipherText = Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    }
}

Answer 1

I am assuming that you are using .Net 4.x, and if so Try this,

if you are not using 4.x then where I have used string interoperlation then you should change that for string.Format("...", ...);

    void Main()
{
    var urlStr = new StringBuilder();
    var url = "http://www.yoursite.com";
    urlStr.Append($"{url}?{BuildQs(Request.QueryString)}");

}

private string BuildQs(System.Collections.Specialized.NameValueCollection collection)
{
    var sb = new StringBuilder();

    foreach (var key in collection.Keys)
    {
        var value = collection[key.ToString()].ToString();
        sb.Append($"{key}={value}");

    }
    var enc = new EncryptDecrypt();
    return enc.Encrypt(sb.ToString());
}

public class EncryptDecrypt
{
    public string Encrypt(string clearText)
    {
        string EncryptionKey = "MAKV2SPBNI99212";
        byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
        using (Aes encryptor = Aes.Create())
        {
            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(clearBytes, 0, clearBytes.Length);
                    cs.Close();
                }
                clearText = Convert.ToBase64String(ms.ToArray());
            }
        }
        return clearText;
    }
    public static string Decrypt(string cipherText)
    {
        string EncryptionKey = "MAKV2SPBNI99212";
        cipherText = cipherText.Replace(" ", "+");
        byte[] cipherBytes = Convert.FromBase64String(cipherText);
        using (Aes encryptor = Aes.Create())
        {
            Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
            encryptor.Key = pdb.GetBytes(32);
            encryptor.IV = pdb.GetBytes(16);
            using (MemoryStream ms = new MemoryStream())
            {
                using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateDecryptor(), CryptoStreamMode.Write))
                {
                    cs.Write(cipherBytes, 0, cipherBytes.Length);
                    cs.Close();
                }
                cipherText = Encoding.Unicode.GetString(ms.ToArray());
            }
        }
        return cipherText;
    }
}