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copied!<p>As far as I've understood your question, you can achieve this using expressions:</p> <pre><code>/// <summary> /// A class with many-many properties /// </summary> class MyClass { public Decimal A { get; set; } public Decimal B { get; set; } public Decimal C { get; set; } } class PropertyHelper<T, TProperty> { private readonly Func<T, TProperty> selector; private readonly Action<T, TProperty> setter; public PropertyHelper(Func<T, TProperty> selector, Action<T, TProperty> setter) { this.selector = selector; this.setter = setter; } public Func<T, TProperty> Selector { get { return selector; } } public Action<T, TProperty> Setter { get { return setter; } } } class AggregateHelper<T, TProperty> { private readonly Dictionary<PropertyInfo, PropertyHelper<T, TProperty>> helpers; public AggregateHelper() { this.helpers = typeof(T) .GetProperties() .Where(p => p.PropertyType == typeof(TProperty)) .ToDictionary(p => p, p => new PropertyHelper<T, TProperty>(MakeSelector(p), MakeSetter(p))); } private Func<T, TProperty> MakeSelector(PropertyInfo property) { var parameterExpr = Expression.Parameter(typeof(T)); var lambda = (Expression<Func<T, TProperty>>)Expression.Lambda( Expression.Property(parameterExpr, property), parameterExpr); return lambda.Compile(); } private Action<T, TProperty> MakeSetter(PropertyInfo property) { var instanceExpr = Expression.Parameter(typeof(T)); var parameterValueExpr = Expression.Parameter(typeof(TProperty)); var lambda = (Expression<Action<T, TProperty>>)Expression.Lambda( Expression.Call(instanceExpr, property.GetSetMethod(), parameterValueExpr), instanceExpr, parameterValueExpr); return lambda.Compile(); } public IEnumerable<PropertyInfo> Properties { get { return helpers.Keys; } } public PropertyHelper<T, TProperty> this[PropertyInfo property] { get { return helpers[property]; } } } </code></pre> <p>Usage: </p> <pre><code> public static void Do() { var target = new MyClass(); var list = new List<MyClass> { new MyClass { A = 1M, B = 2M, C = 3M }, new MyClass { A = 10M, B = 20M, C = 30M }, new MyClass { A = 100M, B = 200M, C = 300M } }; // calculate 'min' for all decimal properties var helper = new AggregateHelper<MyClass, Decimal>(); foreach (var property in helper.Properties) { var propertyHelper = helper[property]; propertyHelper.Setter(target, list.Min(propertyHelper.Selector)); } } </code></pre> <p>Compiled lambdas work faster then reflection, and there will be no boxing/unboxing.</p>

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