Email Validation

 public bool EMailValidation(string _Email)
        {
            
            BoolleanValues = true;
            int IndexofFDot;
            int IndexofLDot;
            int IndexofRate;
            IndexofFDot = _Email.IndexOf(".");
            IndexofLDot = _Email.LastIndexOf(".");
            IndexofRate = _Email.IndexOf("@");
            if (!((IndexofRate < IndexofLDot)
                        && (IndexofRate > 0)))
            {
                BoolleanValues = false;
            }
            if ((System.Text.RegularExpressions.Regex.IsMatch(_Email, "[^a-zA-Z_0-9.@]-") == true))
            {
                BoolleanValues = false;
            }
            return BoolleanValues;
        }