private char[] TextEncrypt(string content, string secretKey) {     char[] data = content.ToCharArray();     char[] key = secretKey.ToCharArray();     for (int i = 0; i < data.Length; i++)     {         data[i] ^= key[i % key.Length];     }     return data; } private string TextDecrypt(char[] data, string secretKey) {     char[] key = secretKey.ToCharArray();     for (int i = 0; i < data.Length; i++)     {         data[i] ^= key[i % key.Length];     }     return new string(data); }