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:: is the scope resolution operator in C, used to access identifiers in the global scope, namespace or class. Global variables, identifiers in a namespace, and member functions or static members of a class can be accessed through the :: operator.
In C:: The role of
Answer:
In C , ::
is a scope resolution operator used to access identifiers in the global scope.
Detailed description:
Global scope
::
operator. Example:
<code class="cpp">int globalVariable = 10; // 全局变量 int main() { // 使用 :: 访问全局变量 std::cout << ::globalVariable << std::endl; // 输出 10 return 0; }</code>
Namespace
::
Also Can be used to access identifiers in a namespace. Example:
<code class="cpp">namespace myNamespace { int num1 = 1; } int main() { // 使用 :: 访问名称空间中的标识符 std::cout << myNamespace::num1 << std::endl; // 输出 1 return 0; }</code>
Class name space
::
It can also be used within a class to access member functions or static members of the class. Example:
<code class="cpp">class MyClass { public: static void print() { std::cout << "Hello from MyClass" << std::endl; } }; int main() { // 使用 :: 访问类成员函数 MyClass::print(); // 输出 "Hello from MyClass" return 0; }</code>
Note:
::
Operation The operator can only be used to access identifiers, not expressions or statements. ::
to refer to itself (that is, ::
is equivalent to this
). The above is the detailed content of The role of :: in c++. For more information, please follow other related articles on the PHP Chinese website!