MATLAB: How do I get the value of a class property given a property name

Question

If I have a class defined as

classdef myclass
  properties
     foo = 3;
     bar = 7;
  end
end

And I want to access property foo I would write

obj = myclass()
obj.foo % Gives me 3

But, if I only have a string representation of the property name, and don't know which property it is how would I do it then? As in the example below:

obj.someFunction('foo')  % or
someFunction(obj, 'foo') % should both give me the value of obj.foo

What I want to do is have a list of properties, iterate through it and get the value for a specific object. It seems like it should be possible, but I failed to find it in the documentation.

score 3 · Accepted Answer · answered Nov 30 '11 at 12:57

3

value = getfield(struct, 'field')

answered Nov 30 '11 at 12:57

Oli

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score 2 · Answer 2 · edited Oct 31 '14 at 11:01

2

You can use:

obj = myclass();
propName = 'foo';
propValue = obj.(propName);

For more information, see Generating Field Names from Variables and Dot-Parentheses.

edited Oct 31 '14 at 11:01

JaBe

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answered Dec 02 '11 at 06:57

Kavka

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score 0 · Answer 3 · answered Nov 30 '11 at 12:59

0

cellfun( @(prop) obj.(prop), properties(obj), 'UniformOutput', false )

answered Nov 30 '11 at 12:59

Edric

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Luckily, `getfield` solved the problem and is a bit less verbose ;) – Hannes Ovrén Nov 30 '11 at 13:41
`getfield` is fine, but `obj.(propname)` is the "modern" way. I was only doing it in a `cellfun` to show how to get all properties in one call. – Edric Nov 30 '11 at 16:57
Ah, I see. After reading Kavkas answer it was much clearer. Thanks! – Hannes Ovrén Dec 02 '11 at 10:31

MATLAB: How do I get the value of a class property given a property name

3 Answers3