C++中的explicit constructor

简单地讲，explicit constructor就是禁止隐式的类型转换，比如下面的代码：

1 #include <iostream> 2  using std::cout; 3 using std::endl; 4 class complexNumbers { 5   double real, img; 6 public: 7   complexNumbers() : real(0), img(0) { } 8   complexNumbers(const complexNumbers& c) { real = c.real; img = c.img; } 9   explicit complexNumbers( double r, double i = 0.0) { real = r; img = i; }10   friend void display(complexNumbers cx);11 };12 void display(complexNumbers cx){13   cout<<"Real Part: "<<cx.real<<" Imag Part: "<<cx.img<<endl;14 }15 int main() {16   complexNumbers one(1);17   display(one);18   complexNumbers two = 2;  //错误！必须显示地进行类型转换19   display(200);            //error: conversion from ‘int’ to non-scalar type ‘complexNumbers’ requested20   return 0;21 }

原文地址：Explicit Constructor in C++
原文链接: https://www.cnblogs.com/edwardlost/archive/2010/11/09/1872862.html

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