carbon/helper.go
2022-05-24 07:03:55 +08:00

81 lines
3.7 KiB
Go
Executable File

package carbon
import (
"bytes"
"time"
)
// common formatting symbols
// 常规格式化符号
var formats = map[byte]string{
'd': "02", // Day: Day of the month, 2 digits with leading zeros. Eg: 01 to 31.
'D': "Mon", // Day: A textual representation of a day, three letters. Eg: Mon through Sun.
'j': "2", // Day: Day of the month without leading zeros. Eg: 1 to 31.
'l': "Monday", // Day: A full textual representation of the day of the week. Eg: Sunday through Saturday.
'F': "January", // Month: A full textual representation of a month, such as January or March. Eg: January through December.
'm': "01", // Month: Numeric representation of a month, with leading zeros. Eg: 01 through 12.
'M': "Jan", // Month: A short textual representation of a month, three letters. Eg: Jan through Dec.
'n': "1", // Month: Numeric representation of a month, without leading zeros. Eg: 1 through 12.
'Y': "2006", // Year: A full numeric representation of a year, 4 digits. Eg: 1999 or 2003.
'y': "06", // Year: A two digit representation of a year. Eg: 99 or 03.
'a': "pm", // Time: Lowercase morning or afternoon sign. Eg: am or pm.
'A': "PM", // Time: Uppercase morning or afternoon sign. Eg: AM or PM.
'g': "3", // Time: 12-hour format of an hour without leading zeros. Eg: 1 through 12.
'h': "03", // Time: 12-hour format of an hour with leading zeros. Eg: 01 through 12.
'H': "15", // Time: 24-hour format of an hour with leading zeros. Eg: 00 through 23.
'i': "04", // Time: Minutes with leading zeros. Eg: 00 to 59.
's': "05", // Time: Seconds with leading zeros. Eg: 00 through 59.
'O': "-0700", // Zone: Difference to Greenwich time (GMT) in hours. Eg: +0200.
'P': "-07:00", // Zone: Difference to Greenwich time (GMT) with colon between hours and minutes. Eg: +02:00.
'T': "MST", // Zone: Timezone abbreviation. Eg: UTC, EST, MDT ...
'c': "2006-01-02T15:04:05-07:00", // Format: ISO 8601 date. Eg: 2004-02-12T15:19:21+00:00.
'r': "Thu, 21 Dec 2000 16:01:07 +0200", // Format: RFC 2822 formatted date. Eg: Thu, 21 Dec 2000 16:01:07 +0200.
}
// converts format to layout.
// format 转 layout
func format2layout(format string) string {
buffer := bytes.NewBuffer(nil)
for i := 0; i < len(format); i++ {
if layout, ok := formats[format[i]]; ok {
buffer.WriteString(layout)
} else {
switch format[i] {
case '\\': // raw output, no parse
buffer.WriteByte(format[i+1])
i++
continue
default:
buffer.WriteByte(format[i])
}
}
}
return buffer.String()
}
// gets a Location instance by a timezone string.
// 通过时区获取 Location 实例
func getLocationByTimezone(timezone string) (*time.Location, error) {
loc, err := time.LoadLocation(timezone)
if err != nil {
err = invalidTimezoneError(timezone)
}
return loc, err
}
// parses as a Duration instance by a duration string.
// 通过时长解析
func parseByDuration(duration string) (time.Duration, error) {
td, err := time.ParseDuration(duration)
if err != nil {
err = invalidDurationError(duration)
}
return td, err
}
// gets absolute value.
// 获取绝对值
func getAbsValue(value int64) int64 {
return (value ^ value>>31) - value>>31
}