public static IFluentContinuation <TViewModel, TPropertyValue> MaxLength <TViewModel, TPropertyValue>(
this IFluentOperator <TViewModel, TPropertyValue> instance, int maxLength)
where TViewModel : ViewModelBase
where TPropertyValue : IComparable <string>, IEquatable <string>
{
var implementerInstance = (FluentImplementer <TViewModel, TPropertyValue>)instance;
implementerInstance.EnsureContextCurrentPropertyIsNotNull();
if (maxLength <= 0)
{
throw new InvalidOperationException("maxLength must be greater than 0");
}
var evaluatedValueProvider = new Func <object>(() =>
{
var value = (string)implementerInstance.Context.CurrentProperty.GetValue();
return(value == null ? 0 : value.Length);
});
var valueProvider = new Func <object>(() => maxLength);
implementerInstance.AddToken(ExpressionNode.OpenParenthesis());
implementerInstance.AddToken(ExpressionNode.LessThanGeneric(evaluatedValueProvider, valueProvider));
implementerInstance.AddToken(ExpressionNode.Or());
implementerInstance.AddToken(ExpressionNode.EqualToGeneric(evaluatedValueProvider, valueProvider));
implementerInstance.AddToken(ExpressionNode.CloseParenthesis());
return((IFluentContinuation <TViewModel, TPropertyValue>)instance);
}