今天小编给大家分享一下Swift如何重构重载运算符的相关知识点,内容详细,逻辑清晰,相信大部分人都还太了解这方面的知识,所以分享这篇文章给大家参考一下,希望大家阅读完这篇文章后有所收获,下面我们一起来了解一下吧。
基础类型 String 为例
重载乘法运算符
将一段字符串重复 n 次拼接在一起;
let c = "abc"*3;
print("c: (c)");//c: abcabcabc
源码实现:
public extension String{
static func * (lhs: String, rhs: Int) -> String {
return String(repeating: lhs, count: rhs);
}
}
对象类型 UIEdgeInsets 为例
重载加法运算符将
将 top, left, bottom, right 属性逐个求和;
let edg1 = UIEdgeInsets(top: 1, left: 2, bottom: 3, right: 4);
let edg2 = UIEdgeInsets(top: 4, left: 3, bottom: 2, right: 1);
let e = edg1 + edg2;
print("edg1: (edg1)");//edg1: UIEdgeInsets(top: 1.0, left: 2.0, bottom: 3.0, right: 4.0)
print("edg2: (edg2)");//edg2: UIEdgeInsets(top: 4.0, left: 3.0, bottom: 2.0, right: 1.0)
print("e: (e)");//e: UIEdgeInsets(top: 5.0, left: 5.0, bottom: 5.0, right: 5.0)
源码实现:
public extension UIEdgeInsets{
static func + (lhs: UIEdgeInsets, rhs: UIEdgeInsets) -> UIEdgeInsets {
return UIEdgeInsets(lhs.top + rhs.top,
lhs.left + rhs.left,
lhs.bottom + rhs.bottom,
lhs.right + rhs.right
);
}
}