这是一个显示 map[time.Time]string“不起作用”的示例。
package main
import (
"fmt"
"time"
)
type MyDate time.Time
func NewMyDate(year, month, day int, tz time.Location) (MyDate, error) {
return MyDate(time.Date(year, time.Month(month), day, 0, 0, 0, 0, &tz)), nil
}
func (md MyDate)ToTime() time.Time {
return time.Time(md)
}
func main() {
timeMap := make(map[time.Time]string)
md1, _ := NewMyDate(2019, 1, 1, *time.UTC)
md2, _ := NewMyDate(2019, 1, 1, *time.UTC)
timeMap[md1.ToTime()] = "1"
timeMap[md2.ToTime()] = "2"
for k, v := range timeMap {
fmt.Println(k, v)
}
}
输出:
2019-01-01 00:00:00 +0000 UTC 1
2019-01-01 00:00:00 +0000 UTC 2
最佳答案
func NewMyDate(year, month, day int, tz time.Location) (MyDate, error) { return MyDate(time.Date(year, time.Month(month), day, 0, 0, 0, 0, &tz)), nil }
&tz
是指NewMyDate
参数的地址,每次调用可能不一样。在 Go 中,函数参数按值传递。
每次调用都使用相同的时区。例如,
package main
import (
"fmt"
"time"
)
type MyDate time.Time
func NewMyDate(year, month, day int, tz *time.Location) (MyDate, error) {
return MyDate(time.Date(year, time.Month(month), day, 0, 0, 0, 0, tz)), nil
}
func (md MyDate) ToTime() time.Time {
return time.Time(md)
}
func main() {
timeMap := make(map[time.Time]string)
md1, _ := NewMyDate(2019, 1, 1, time.UTC)
md2, _ := NewMyDate(2019, 1, 1, time.UTC)
timeMap[md1.ToTime()] = "1"
timeMap[md2.ToTime()] = "2"
for k, v := range timeMap {
fmt.Println(k, v)
}
}
Playground :https://play.golang.org/p/M10Xn4jsoKS
输出:
2019-01-01 00:00:00 +0000 UTC 2
关于datetime - 为什么 map[time.Time]string 有时不起作用?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54147939/