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POHow to instantiate different child classes conditionally?
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copied!<p>For example, in the main function, I want to get the user's input. Depending on the input, I will create either a <code>Rectangle</code> or a <code>Circle</code>, which are child classes of <code>Object</code>. If there's no input (or unknown), then I will just create a generic object. </p> <pre><code>class Object { public: Object(); void Draw(); private: .... }; class Rectangle:public Object { public: Rectangle(); .... //it might have some additional functions private: .... }; class Circle:public Object { public: Circle(); .... //it might have some additional functions private: .... }; </code></pre> <p>main function:</p> <pre><code>string objType; getline(cin, objType); if (!objType.compare("Rectangle")) Rectangle obj; else if (!objType.compare("Circle")) Circle obj; else Object obj; obj.Draw(); </code></pre> <p>Of course, the code above won't work because I can't instantiate an object inside an If statement. So i tried something like this.</p> <pre><code>Object obj; if (!objType.compare("Rectangle")) obj = Rectangle(); else if (!objType.compare("Circle")) obj = Circle(); obj.Draw(); </code></pre> <p>This code would compile, but it won't do what I want. For some reason, the object was not initiated the way the child class should (for example, I set the some Object's member variables, specifically, a vector, differently in the child classes). However, when I put a break point at the Child class constructor, it did run through there. </p> <p>So how should I put instantiate Objects as its child classes in some if-statements??</p>

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