运算符重载

发表于2022-06-24更新于2022-06-25

运算符重载

运算符重载用于拓展运算符的作用对象至任意对象

一元运算符（！，）

-[负号]

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BIG operator - ()  
{
    BIG c;
    c.x = -x;
    return c;
}

二元运算符（-，*，/）

注意顺序

+

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BIG operator + (const BIG &b)
{
	Box c;
    c.x = x + b.x;
    return c;
}

赋值运算符

=

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void operator = (const BIG &b)
{
    x = b.x;
}

输入/输出运算符

<<

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friend ostream &operator << ( ostream &out, const BIG &p )                                 
{ 
    out << p.x:
    return out;            
}

>>

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friend istream &operator >> ( istream &in, BIG &p )
{ 
    in >> p.x;
    return in;            
}

递增递减运算符

++A

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BIG operator ++ ()  
{
    BIG c;
    x++;			//先加加
    c.x = x;
    return c;
}

A++

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BIG operator ++ ( int )         
{
	BIG c;			//保留原来的值
    c.x = x;
    x++;			//加加
	return c;		//返回原来值
}

类型转换运算符

(类型)

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operator char( )
{
    char c;
    c = a + 'A'
    return c;
}