public static Expression <Func <TEntity, bool> > ToLambda <TEntity>(this PropertyInfo pi, bool compare)
{
ParameterExpression item = Expression.Parameter(typeof(TEntity), "item");
FilterDescriptor fd = new FilterDescriptor(pi.Name, FilterOperator.IsEqualTo, compare);
Expression expression = fd.GetEqualityExpression(item);
Expression <Func <TEntity, bool> > lambda = Expression.Lambda <Func <TEntity, bool> >(expression, item);
return(lambda);
}