How to encrypt a string using c#

The following cose sample shows how to encrypt a string using c#
private string encryptString(string strToEncrypt)
{
System.Text.UTF8Encoding ue = new System.Text.UTF8Encoding();
byte[] bytes = ue.GetBytes(strToEncrypt);

// encrypt bytes
System.Security.Cryptography.MD5CryptoServiceProvi der md5 = new System.Security.Cryptography.MD5CryptoServiceProvi der();
byte[] hashBytes = md5.ComputeHash(bytes);

// Convert the encrypted bytes back to a string (base 16)
string hashString = "";

for(int i=0;i{
hashString += Convert.ToString(hashBytes[i],16).PadLeft(2,'0');
}

return hashString.PadLeft(32,'0');
}