12.6 In C++, the code "MyClass ht;" creates an object ht on the stack frame. But in C#, this same code compiles, but gives a runtime error. Why? |
MyClass ht; does not create any object. Instead, it creates a variable (a reference) of type MyClass, and sets its value to null. No object is created. To create an object, you need to explicitly call the class constructor with a new. |
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| MyClass ht = new MyClass();
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You can also use ht to refer to an instance of MyClass that has been created (with a new) at some other point in your code. |
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| MyClass myClass = new MyClass();
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| ......
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| MyClass ht;
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| ......
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| ht = myClass; // both ht and myClass are references to the same object...
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