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Golang 实现结构体数组按多字段排序 php 排序写法近期因项目重构（php->golang），涉及到一些将对象列表中的对象按不同的字段（属性）排序；在 php 中，可以使用 usort + 自定义的排序函数轻松实现；PHP usort 官方文档下面我们先看一个在 php 中的例子: 下面是一个待排序待数组<?php $result = array( array( "val" => "f", "mtime" => 1595144638, "orderval"=>4 ), array( "val" => "d", "mtime" => 1595144646, "orderval"=>2 ), array( "val" => "a", "mtime" => 1595144648, "orderval"=>8 ), array( "val" => "t", "mtime" => 1595144648, "orderval"=>5 ), array( "val" => "e", "mtime" => 1595144650, "orderval"=>3 ) );我们目前待目标是将该数组中待对象按 mtime 从大到小排序；如果 mtime 字段的值相等，则按 orderval 从大到小排，最终想要的结果为：e,a,t,d,f[ {"val"=>"e","mtime"=>1595144650,"orderval"=>3}, {"val"=>"a","mtime"=>1595144648,"orderval"=>8}, {"val"=>"t","mtime"=>1595144648,"orderval"=>5}, {"val"=>"d","mtime"=>1595144646,"orderval"=>2}, {"val"=>"f","mtime"=>1595144638,"orderval"=>4} ] 我们首先定义一个自定义函数，然后巧妙使用 usort 函数去调用的自定义函数，最终实现目标，直接上代码：php $result = array( array( "val" => "f", "mtime" => 1595144638, "orderval"=>4 ), array( "val" => "d", "mtime" => 1595144646, "orderval"=>2 ), array( "val" => "a", "mtime" => 1595144648, "orderval"=>8 ), array( "val" => "t", "mtime" => 1595144648, "orderval"=>5 ), array( "val" => "e", "mtime" => 1595144650, "orderval"=>3 ) ); //按mtime 从大到小；如果mtime 相等，则按orderval 从大到小; usort($result, function ($v1, $v2) { if ($v1['mtime'] < $v2['mtime'] || ($v1['mtime'] == $v2['mtime'] && $v1['orderval'] < $v2['orderval'])) { return 1; } else { return -1; } }); var_dump($result); 运行结果：array(5) { [0]=> array(3) { ["val"]=> string(1) "e" ["mtime"]=> int(1595144650) ["orderval"]=> int(3) } [1]=> array(3) { ["val"]=> string(1) "a" ["mtime"]=> int(1595144648) ["orderval"]=> int(8) } [2]=> array(3) { ["val"]=> string(1) "t" ["mtime"]=> int(1595144648) ["orderval"]=> int(5) } [3]=> array(3) { ["val"]=> string(1) "d" ["mtime"]=> int(1595144646) ["orderval"]=> int(2) } [4]=> array(3) { ["val"]=> string(1) "f" ["mtime"]=> int(1595144638) ["orderval"]=> int(4) } }那么同样的功能，如果要用 golang 来实现，应如何办呢？golang 排序下面我们首先讲讲 golang 官方对排序 对支持，然后给出具体对例子;package main import ( "fmt" "sort" ) type Obj struct { Var string `json:"var"` Mtime int `json:"mtime"` Orderval int `json:"orderval"` } type List []Obj func (p List) Len() int { return len(p) } // 此处排序是从大到小的， 如果想升序，可以把此方法里的 判定 改为 相反的判定即可 func (p List) Less(i, j int) bool { if p[i].Mtime > p[j].Mtime { return true } if p[i].Mtime < p[j].Mtime { return false } return p[i].Orderval > p[j].Orderval } func (p List) Swap(i, j int) { p[i], p[j] = p[j], p[i] } func (p *List) Sort() { sort.Sort(p) } func main() { s := List{{"f", 1595144638, 4}, {"d", 1595144646, 2}, {"a", 1595144648, 8}, {"t", 1595144648, 5}, {"e", 1595144650, 3}} fmt.Println(s) s.Sort() fmt.Println(s) } // 如果想使用传入的方法来写，可以把main 方法 的写法改为下边这个 //func toSortAsc(UserList []Obj)[]Obj{ // s := List{} // for _,v := range UserList{ // s = append(s,v) // } // s.Sort() // return s //} 再举一个简单的例子package main import ( "fmt" "sort" ) type Instance struct { Domain string `json:"domain"` Ip string `json:"ip"` Containers []string `json:"containers,omitempty"` } func main() { instances := make([]*Instance, 0, 10) i1 := &Instance{} i1.Domain = "zhap" i1.Ip = "1" instances = append(instances, i1) i2 := &Instance{} i2.Domain = "abc" i2.Ip = "2" instances = append(instances, i2) i3 := &Instance{} i3.Domain = "mid" i3.Ip = "3" instances = append(instances, i3) fmt.Println("排序前 ") for _, v := range instances { fmt.Println(*v) } sort.Slice(instances, func(i, j int) bool { return instances[i].Domain < instances[j].Domain }) fmt.Println("排序后 ") for _, v := range instances { fmt.Println(*v) } }
