添加N周前后方法

README.md

@@ -164,6 +164,15 @@ c.Now().SubMonths(3).ToDateTimeString() // 2020-06-08 13:00:00
 // 一月前
 c.Now().SubMonth().ToDateTimeString() // 2020-08-08 13:00:00
 
+// 三周后
+c.Now().AddWeeks(3).ToDateTimeString() // 2020-09-29 13:00:00
+// 一周后
+c.Now().AddWeek().ToDateTimeString() // 2020-09-15 13:00:00
+// 三周前
+c.Now().SubWeeks(3).ToDateTimeString() // 2020-08-17 13:00:00
+// 一周前
+c.Now().SubWeek().ToDateTimeString() // 2020-09-01 13:00:00
+
 // 三天后
 c.Now().AddDays(3).ToDateTimeString() // 2020-09-11 13:00:00
 // 一天后

carbon.go

@@ -120,6 +120,30 @@ func (c *Carbon) SubMonth() *Carbon {
 	return c
 }
 
+// AddWeeks N周后
+func (c *Carbon) AddWeeks(weeks int) *Carbon {
+	c.Time = c.Time.AddDate(0, 0, weeks*7)
+	return c
+}
+
+// AddWeek 1周后
+func (c *Carbon) AddWeek() *Carbon {
+	c.Time = c.Time.AddDate(0, 0, 7)
+	return c
+}
+
+// SubWeeks N周前
+func (c *Carbon) SubWeeks(weeks int) *Carbon {
+	c.Time = c.Time.AddDate(0, 0, -weeks*7)
+	return c
+}
+
+// SubMonth 减少1月
+func (c *Carbon) SubWeek() *Carbon {
+	c.Time = c.Time.AddDate(0, 0, -7)
+	return c
+}
+
 // AddDays N天后
 func (c *Carbon) AddDays(days int) *Carbon {
 	c.Time = c.Time.AddDate(0, 0, days)