this pointer
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Im Inneren nicht-statische Member-Funktion einen Zeiger auf die Klasse Objekt, von dem die Funktion aufgerufen wurde .
Original:
Inside non-static member function, holds a pointer to the class object from which the function was invoked.
The text has been machine-translated via Google Translate.
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Die Art der this Zeiger
cv T* const wo T der Name der Klasse ist und cv bezieht sich auf die cv Planer der Funktion der Zeiger in. Zum Beispiel verwendet wird:Original:
The type of this pointer is
cv T* const where T is the class name and cv refers to the cv Planer of the function the pointer is used in. For example:The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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| Function signature | Type of this |
|---|---|
| void T::foo() | T*const this; |
| void T::foo()const | const T*const this; |
| void T::foo()volatile | volatile T*const this; |
| void T::foo()constvolatile | constvolatile T*const this; |
[Bearbeiten]Beispiel
class T {int x; void foo(){ this->x =5;// this used explicitly x =6;// same as this->x = 6;} void foo()const{ this->x =7;// Error: *this is constant} void foo (int x ){// parameter x shadows the attribute with the same name this->x = x;// unqualified x refers to the parameter, but the attribute is still accessible using the this pointer } T& operator=(const T& b ){ x = b.x;return*this;// this is often used when a reference to the current object is needed} void bar (const T& b ){// two ways to call class operators using this (*this)= b; this->operator=( b );} void bar(){// methods can be called even when there's no object// the this pointer can be seen like an additional parameter implicitly passedif( this ==NULL)return;}}; T* pointer =reinterpret_cast<T*>(123); pointer->bar();// bar is called with 123 (0x7B) as value for this
