C# – Get String Name of Property Using Reflection

c++propertyinforeflection

There is a whole wealth of reflection examples out there that allow you to get either:

  1. All properties in a class
  2. A single property, provided you know the string name

Is there a way (using reflection, TypeDescriptor, or otherwise) to get the string name of a property in a class at runtime, provided all I have is an instance of the class and property?

I have an instance of the class with the property (as well as other properties) that I want to get the string name of (not the getter/setter). I need to do some work on that property using Reflection, but don't want to maintain code with hardcoded string names in case I refactor the property name. Thus, I want to programatically get the name of the property.

I know that I can easily get all the properties in a class using reflection and then get the name of each property. What I'm asking for is a function to give me name of a property, provided I pass it the instance of the property. In other words, how do I find the property I want from the PropertyInfo[] array returned to me from the class.GetType().GetProperty(myProperty) so that I can get the PropertyInfo.Name from it?

Best Answer

If you already have a PropertyInfo, then @dtb's answer of using PropertyInfo.Name is the right way. If, however, you're wanting to find out which property's code you're currently in, you'll have to traverse the current call stack to find out which method you're currently executing and derive the property name from there.

var stackTrace = new StackTrace();
var frames = stackTrace.GetFrames();
var thisFrame = frames[0];
var method = thisFrame.GetMethod();
var methodName = method.Name; // Should be get_* or set_*
var propertyName = method.Name.Substring(4);

If you don't have a PropertyInfo object, you can get that from a property expression, like this:

public static string GetPropertyName<T>(Expression<Func<T>> propertyExpression)
{
    return (propertyExpression.Body as MemberExpression).Member.Name;
}

To use it, you'd write something like this:

var propertyName = GetPropertyName(
    () => myObject.AProperty); // returns "AProperty"