fix(outputer): fix #328

Author: kuafuRace

outputer.go

@@ -794,6 +794,12 @@ func (c *Carbon) Format(format string, timezone ...string) string {
 				buffer.WriteString(strconv.FormatInt(c.TimestampMicro(), 10))
 			case 'X': // timestamp with nanoseconds, such as 1596604455000000000
 				buffer.WriteString(strconv.FormatInt(c.TimestampNano(), 10))
+			case 'u':
+				buffer.WriteString(fmt.Sprintf("%03d", c.Millisecond()))
+			case 'v':
+				buffer.WriteString(fmt.Sprintf("%06d", c.Microsecond()))
+			case 'x':
+				buffer.WriteString(fmt.Sprintf("%09d", c.Nanosecond()))
 			default: // common symbols
 				buffer.WriteString(c.StdTime().Format(layout))
 			}

outputer_unit_test.go

@@ -2,6 +2,7 @@ package carbon
 
 import (
 	"testing"
+	"time"
 
 	"github.com/stretchr/testify/suite"
 )
@@ -1778,6 +1779,16 @@ func (s *OutputerSuite) TestCarbon_Format() {
 		s.Equal("1596633255999999", Parse("2020-08-05 13:14:15.999999999").Format(TimestampMicroFormat))
 		s.Equal("1596633255999999999", Parse("2020-08-05 13:14:15.999999999").Format(TimestampNanoFormat))
 	})
+
+	// https://github.com/dromara/carbon/issues/328
+	s.Run("issue328", func() {
+		inputTime := time.Date(2026, 1, 22, 11, 30, 52, 624_225_666, time.UTC)
+		c := CreateFromStdTime(inputTime)
+
+		s.Equal(inputTime.Format("2006-01-02 15:04:05.999"), c.Format("Y-m-d H:i:s.u"))
+		s.Equal(inputTime.Format("2006-01-02 15:04:05.999999"), c.Format("Y-m-d H:i:s.v"))
+		s.Equal(inputTime.Format("2006-01-02 15:04:05.999999999"), c.Format("Y-m-d H:i:s.x"))
+	})
 }
 
 func (s *OutputerSuite) TestFormat2Layout() {