I want to get the PropertyInfo for a specific property. I could use:
foreach(PropertyInfo p in typeof(MyObject).GetProperties())
{
if ( p.Name == "MyProperty") { return p }
}
But there must be a way to do something similar to
typeof(MyProperty) as PropertyInfo
Is there? Or am I stuck doing a type-unsafe string comparison?
Cheers.
There is a .NET 3.5 way with lambdas/Expression that doesn't use strings...
using System;
using System.Linq.Expressions;
using System.Reflection;
class Foo
{
public string Bar { get; set; }
}
static class Program
{
static void Main()
{
PropertyInfo prop = PropertyHelper<Foo>.GetProperty(x => x.Bar);
}
}
public static class PropertyHelper<T>
{
public static PropertyInfo GetProperty<TValue>(
Expression<Func<T, TValue>> selector)
{
Expression body = selector;
if (body is LambdaExpression)
{
body = ((LambdaExpression)body).Body;
}
switch (body.NodeType)
{
case ExpressionType.MemberAccess:
return (PropertyInfo)((MemberExpression)body).Member;
default:
throw new InvalidOperationException();
}
}
}
You can use the new nameof() operator that is part of C# 6 and available in Visual Studio 2015. More info here.
For your example you would use:
PropertyInfo result = typeof(MyObject).GetProperty(nameof(MyObject.MyProperty));
The compiler will convert nameof(MyObject.MyProperty) to the string "MyProperty" but you gain the benefit of being able to refactor the property name without having to remember to change the string because Visual Studio, ReSharper, and the like know how to refactor nameof() values.
