C# Calling a Variable from another Variable

Question

public class Car
 {
     public string Color { get; set; }
     public string Model { get; set; }
 }

How I call "Car.Color" or "Car.Model" from a variable?

Ex.

string MyVariable = "Color";
MyListBox.Items.Add(Car.Model); //It Works Ok
MyListBox.Items.Add(Car.MyVariable); // How??

Regards.

Just to clarify anyone else (it took me a min to figure out) I think he is asking about using reflection to search for the property selected in `MyVariable` and add that to the list box. — Scott Chamberlain, Jun 28 '13 at 18:02
Are you using Winforms or WPF? Binding is the solution to this, but it is different depending on which you are using. — Scott Chamberlain, Jun 28 '13 at 18:02
What are you trying to do? you Could do Color MyColor = Car.Color; maybe if thats your goal. — Bit, Jun 28 '13 at 18:04
possible duplicate of [Get property value by string](http://stackoverflow.com/questions/11390697/get-property-value-by-string) — Rob Kennedy, Jun 28 '13 at 18:05
I'm using Winforms. Car (more complex) is a query's result (LINQ to Dataset). Thanks. — karmany, Jun 28 '13 at 18:08

Jon Skeet · Accepted Answer · 2013-06-28T20:25:49.920

11

You'd have to use reflection. For example:

var property = typeof(Car).GetProperty(MyVariable);
MyListBox.Items.Add(property.GetValue(Car)); // .NET 4.5

Or:

var property = typeof(Car).GetProperty(MyVariable);
MyListBox.Items.Add(property.GetValue(Car, null)); // Prior to .NET 4.5

(Your sample code would be clearer if you used a different name for the variable Car than the type Car, mind you. Ditto MyVariable which doesn't look like a variable in normal .NET naming conventions.)

edited Jun 28 '13 at 20:25

answered Jun 28 '13 at 18:01

Jon Skeet

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@karmany: It's worth noting that this is the sort of thing you don't want to be doing most of the time. We don't really have enough context to know whether it's the most appropriate approach *here*, or whether binding would be better as Scott suggested. – Jon Skeet Jun 28 '13 at 18:04
Car is a query's result (LINQ to Dataset). When a user selects "Color" Field (in the query), I want to fill a list (MyListBox) only with the "Color" Field. – karmany Jun 28 '13 at 18:16
2

@karmany : Then that sounds like you *should* be using binding instead. Set the display property based on the query, but actually populate the listbox with the full `Car` references. – Jon Skeet Jun 28 '13 at 18:17
Jon, your code shows: "No overload for GetValue method..." I don't know what is "binking instead". I will seek more information. – karmany Jun 28 '13 at 18:31
yeah this seems like using symbolic references in Perl... tread carefully. – gudatcomputers Jun 28 '13 at 18:33
This code works fine: var property = typeof(Car).GetProperty(MyVariable); MyListBox.Items.Add(property.GetValue(Car,null)); if you could edit your answer. Very thanks!! – karmany Jun 28 '13 at 19:04
@karmany : My code should work fine in .NET 4.5; the overload was added then. I'll edit the answer to make that clear. – Jon Skeet Jun 28 '13 at 20:25

C# Calling a Variable from another Variable

1 Answers1