HOW TO ENCRYPT AND DECRYPT A STRING IN C#

string EncryptedString= Encrypt("STRING VALUE");

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public string Encrypt(string Data)
{
 SHA1Managed shaM = new SHA1Managed();
 Convert.ToBase64String(shaM.ComputeHash(System.Text.Encoding.ASCII.GetBytes(Data)));
 byte[] eNC_data = System.Text.ASCIIEncoding.ASCII.GetBytes(Data);
 string eNC_str = Convert.ToBase64String(eNC_data);
 return eNC_str;
}

string  DecryptedString= Decrypt("Encryptedsrting");

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string original_string=Decrypt(eNC_str);

private string Decrypt(string Data)
{
 byte[] dEC_data = Convert.FromBase64String(Data);
 string dEC_Str = System.Text.ASCIIEncoding.ASCII.GetString(dEC_data);
 return dEC_Str;
}