英文:
what is the best way to check if a string is date value?
问题
反射似乎对时间类型不起作用。在这里，最好的方法是什么？
package mainimport ("fmt""reflect""time")func main() {stringDate := "07/26/2020"// 将字符串日期解析为Go语言的时间类型t, _ := time.Parse("01/02/2006", stringDate)ts := ""ts = t.String()v := reflect.ValueOf(ts)fmt.Println(ts) // 输出 "2020-07-26 00:00:00 +0000 UTC"fmt.Println(v.Type()) // 输出 "string"。我如何将其转换为time.Time类型？}
英文:
Reflection does not seem to be working for time. What is the best approach here?
package mainimport ("fmt""reflect""time")func main() {stringDate := "07/26/2020"// parse string date to golang timet, _ := time.Parse("01/02/2006", stringDate)ts := ""ts = t.String()v := reflect.ValueOf(ts)fmt.Println(ts) // prints "2020-07-26 00:00:00 +0000 UTC"fmt.Println(v.Type()) // prints "string". How do I get this to time.Time ?}
答案1
得分: 2
当你使用time.Parse时，你已经在检查stringDate是否是一个有效的日期，并将其解析为time.Time。你真正需要做的是在解析日期时检查err。
示例：
stringDate := "not a date"// 将字符串日期解析为golang时间t, err := time.Parse("01/02/2006", stringDate)if err != nil {fmt.Println(err)return}fmt.Println("Time: ", t, "Type of t: ", reflect.ValueOf(t).Type())
这将打印出：
parsing time "not a date" as "01/02/2006": cannot parse "not a date" as "01"
但是，如果提供一个有效的日期，将会打印出：
Time: 2012-03-07 00:00:00 +0000 UTC Type of t: time.Time
你可以在这里找到可工作的示例。
英文:
When you use time.Parse you are checking already if the stringDate is a valid date and you are parsing it to time.Time. What you really need is to check for err when parsing the date.
Example:
stringDate := "not a date"// parse string date to golang timet, err := time.Parse("01/02/2006", stringDate)if err != nil {fmt.Println(err)return}fmt.Println("Time: ", t, "Type of t: ", reflect.ValueOf(t).Type())
Which would print out
parsing time "not a date" as "01/02/2006": cannot parse "not a date" as "01"
But providing a valid date will result in printing out:
Time: 2012-03-07 00:00:00 +0000 UTC Type of t: time.Time
The working example you can find here
答案2
得分: 1
这似乎可以实现：
package mainimport "time"func isDateValue(stringDate string) bool {_, err := time.Parse("01/02/2006", stringDate)return err == nil}func main() {ok := isDateValue("07/26/2020")println(ok)}
英文:
This seems to do it:
package mainimport "time"func isDateValue(stringDate string) bool {_, err := time.Parse("01/02/2006", stringDate)return err == nil}func main() {ok := isDateValue("07/26/2020")println(ok)}
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