c++ - C++指针声明和赋值

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What are the barriers to understanding pointers and what can be done to overcome them? [closed]
                                
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int num1 = 8;   //okay
int *pointer;   //okay
*pointer = &num1;   //NOT okay, compiler says (Error:a value of type int* cannot be
                    //assigned to an entity of type "int")

int num2 = 8;   //okay
int *pointer = &num2;   //okay

我很困惑为什么第一部分给出错误而第二部分没有给出错误，它们在我看来是相同的

最佳答案

在赋值语句中：

*pointer = &num1;   //NOT okay

*pointer是pointer指向的值，类型为int，&num1是num1的地址，类型为int*。正如编译器所说，您不能将指针分配给整数。

pointer = &num1或*pointer = num1都可以，取决于您是要修改指针本身还是指向指针的值。

在声明中：

int *pointer = &num2;   //okay

尽管外观与赋值语句相似，但这会初始化pointer而不是*pointer。它声明pointer为指针，其类型与int*相同。

关于c++ - C++指针声明和赋值，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/24777782/