Different methods for instantiating an object in C++
What is the difference between this:
Myclass *object = new Myclass();
and
Myclass object = new Myclass();
I have seen that a lot of C++ libraries like wxWidgets, OGRE etc use the first method... Why?
The second is wrong !
You may use
MyClass object;
That will work.
Now, concerning how to choose between these two possibilities, it mainly depends on how long your object should live. See there for a thorough answer.
Myclass *object = new Myclass(); //object is on the heap
Myclass object; //object is on the stack
如果您计划在很长一段时间内使用这些对象，并且您在堆栈上创建对象的时间较短（或范围），则可以在堆上创建对象。
Your first line is 100% correct. Unfortunately, you can't create object with your second line in c++. There are two ways to make/create an object in c++.
First one is :
MyClass myclass; // if you only need to call the default constructor
MyClass myclass(12); // if you need to call constructor with parameters*
Second one is :
MyClass *myclass = new MyClass();// if you only need to call the default constructor
MyClass *myclass = new MyClass(12);// if you need to call constructor with parameters
In c++ if you use the new keyword, object will be stored in heap. It's very useful if you are using this object for a long time period and if you use first method, it will be stored in stack. it can be used only short time period. Notice: if you use new keyword, remember it will return pointer value. You should declare name with * . If you use second method, it doesn't delete object in the heap. You must delete by yourself using delete keyword:
delete myclass;
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