C++学习-2023/12/13-C++类型转换

C++类型转换

static_cast

类似C语言强制类型转换
1.可以用做基本数据类型转换
2.把空类型的指针转换为目标指针类型
3.不能转换带有const属性指针

const_cast

提供一个常属性的接口

reinterpret_cast

说基本没用到

dynamic_cast:多态才会接触到

#include <iostream>
struct MM
{char* name;int age;void setData(const char* mmName, int mmAge){name = const_cast<char*>(mmName);age = mmAge;}void printfData(){std::cout << name << "\t" << age << std::endl;}};//1.基本类型转换
void TestTransform()
{//1.基本类型转换//Cint cnum = (int)1.1;std::cout << cnum << "\n";//C++方式int cppNum = int(1.2);std::cout << cnum << "\n";
}void TestStatic_cast()
{//C++提供的安全double dNum = 1.11;//static_cast<要转换的类型>（要转换的东西：表达式也可以）int num = static_cast<int>(dNum);std::cout << dNum << "\n";//const类型转换：增加constdouble eNum= 2.22;const int fNum = static_cast<const int>(eNum);std::cout << fNum << "\n";const int cData = 1;//错误用法//int* pData = static_cast<int*>(&cData);int* pData = const_cast<int*>(&cData);std::cout << (*pData)+2000 << "\n";MM m1;m1.setData("喜德盛", 19);m1.printfData();char name[20] = "永久";MM m2;m2.setData(name, 18);m2.printfData();
}int main()
{std::cout << "Hello World!\n";TestStatic_cast();}