How to create an object using class name

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Sylvain
Sylvain 2020-2-18
评论： Sylvain 2020-2-21
In my function, I am getting the class name from an object to create a new one. What is the right syntax to creat the new Object ?
function newObj = createNewObject(obj)
className = class(obj);
newObj = className();
end

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采纳的回答

Matt J
Matt J 2020-2-18
function newObj = createNewObject(obj)
newObj = feval( class(obj) );
end

更多回答（2 个）

Sky Sartorius
Sky Sartorius 2020-2-18
A quick and dirty approach that will work in many cases is to use eval:
function new = createNewObjectOfThisClass(original)
new = eval([class(original) '.empty;']);
end
Image Analyst
Image Analyst 2020-2-18
That won't work for all types of objects, like structures, other custom-designed classes, etc. I think your best bet is to just make a copy of the variable
function newObj = createNewObject(obj)
newObj = obj;
end
It will have the values of the input object, but more importantly, it will inherit all the fields, properties, and methods of your input class. As you can see you actually don't even need this function at all since it's just a wrapper than essentially does nothing. You could just simply do this
newObj = obj;
rather than this
newObj = createNewObject(obj)
  1 个评论
Matt J
Matt J 2020-2-18
编辑：Matt J 2020-2-18
I disagree. It's often necessary to call the constructor to instantiate a new, independent version of the original object. For example, if obj is an object of a handle class then
newObj = obj
does not give you an indepedent copy of obj. Just another handle to its property data.

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