It sounds like you're sorted with regular reflection, but for info, the code to build an expression for nested properties would be very similar to this order-by code.
Note that to set a value, you need to use GetSetMethod()
on the property and invoke that - there is no inbuilt expression for assigning values after construction (although it is supported in 4.0).
(edit) like so:
using System;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
class Foo
{
public Foo() { Bar = new Bar(); }
public Bar Bar { get; private set; }
}
class Bar
{
public string Name {get;set;}
}
static class Program
{
static void Main()
{
Foo foo = new Foo();
var setValue = BuildSet<Foo, string>("Bar.Name");
var getValue = BuildGet<Foo, string>("Bar.Name");
setValue(foo, "abc");
Console.WriteLine(getValue(foo));
}
static Action<T, TValue> BuildSet<T, TValue>(string property)
{
string[] props = property.Split('.');
Type type = typeof(T);
ParameterExpression arg = Expression.Parameter(type, "x");
ParameterExpression valArg = Expression.Parameter(typeof(TValue), "val");
Expression expr = arg;
foreach (string prop in props.Take(props.Length - 1))
{
// use reflection (not ComponentModel) to mirror LINQ
PropertyInfo pi = type.GetProperty(prop);
expr = Expression.Property(expr, pi);
type = pi.PropertyType;
}
// final property set...
PropertyInfo finalProp = type.GetProperty(props.Last());
MethodInfo setter = finalProp.GetSetMethod();
expr = Expression.Call(expr, setter, valArg);
return Expression.Lambda<Action<T, TValue>>(expr, arg, valArg).Compile();
}
static Func<T,TValue> BuildGet<T, TValue>(string property)
{
string[] props = property.Split('.');
Type type = typeof(T);
ParameterExpression arg = Expression.Parameter(type, "x");
Expression expr = arg;
foreach (string prop in props)
{
// use reflection (not ComponentModel) to mirror LINQ
PropertyInfo pi = type.GetProperty(prop);
expr = Expression.Property(expr, pi);
type = pi.PropertyType;
}
return Expression.Lambda<Func<T, TValue>>(expr, arg).Compile();
}
}
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