You have to use Enum.Parse to get the object value from Enum, after that you have to change the object value to specific enum value. Casting to enum value can be do by using Convert.ChangeType. Please have a look on following code snippet
public T ConvertStringValueToEnum<T>(string valueToParse){
return Convert.ChangeType(Enum.Parse(typeof(T), valueToParse, true), typeof(T));
}