Encrypt Decrypt string using C# and VB.net in ASP.Net

Hi SajidHussa,

Refer below sample.

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    string text = "Welcome to ASPForums.";
    string encryptedString = EncryptString(text);
    string decryptedString = DecryptString(encryptedString);
    Response.Write(string.Format("Encrypted Value : {0}{1}Decrypted Value : {2}", encryptedString, Environment.NewLine, decryptedString));
}

public string EncryptString(string text)
{
    string encrypted = "";
    byte[] bytes;
    try
    {
        bytes = new byte[text.Length];
        bytes = System.Text.Encoding.UTF8.GetBytes(text);
        encrypted = Convert.ToBase64String(bytes);
    }
    catch (Exception ex)
    {
        encrypted = "";
    }

    return encrypted;
}

public string DecryptString(string encrString)
{
    byte[] bytes;
    string decrypted;
    try
    {
        bytes = Convert.FromBase64String(encrString);
        decrypted = System.Text.ASCIIEncoding.ASCII.GetString(bytes);
    }
    catch (FormatException fe)
    {
        decrypted = "";
    }

    return decrypted;
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    Dim text As String = "Welcome to ASPForums."
    Dim encryptedString As String = EncryptString(text)
    Dim decryptedString As String = DecryptString(encryptedString)
    Response.Write(String.Format("Encrypted Value : {0}{1}Decrypted Value : {2}", encryptedString, Environment.NewLine, decryptedString))
End Sub

Public Function EncryptString(ByVal text As String) As String
    Dim encrypted As String = ""
    Dim bytes As Byte()
    Try
        bytes = New Byte(text.Length - 1) {}
        bytes = System.Text.Encoding.UTF8.GetBytes(text)
        encrypted = Convert.ToBase64String(bytes)
    Catch ex As Exception
        encrypted = ""
    End Try

    Return encrypted
End Function

Public Function DecryptString(ByVal encrString As String) As String
    Dim bytes As Byte()
    Dim decrypted As String
    Try
        bytes = Convert.FromBase64String(encrString)
        decrypted = System.Text.ASCIIEncoding.ASCII.GetString(bytes)
    Catch fe As FormatException
        decrypted = ""
    End Try

    Return decrypted
End Function

Screenshot