public void AddRule <T>(Expression <Func <T> > expression, Func <bool> rule, string message)
{
var propertyName = GetPropertyName(expression);
if (_ruleMap.ContainsKey(propertyName))
{
_ruleMap[propertyName].AddRule(rule, message);
}
else
{
var binder = new Binder(propertyName);
binder.AddRule(rule, message);
_ruleMap.TryAdd(propertyName, binder);
}
}