From ecff6cccc2b011864808d4875444073d151c212e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E6=87=92=E5=BE=97=E5=8B=A4=E5=BF=AB?=
 <20254980+ldqk@users.noreply.github.com>
Date: Thu, 3 Sep 2020 16:54:30 +0800
Subject: [PATCH] Update README.md

---
 README.md | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/README.md b/README.md
index ce09ec8..c4377cd 100644
--- a/README.md
+++ b/README.md
@@ -973,6 +973,7 @@ var table=list.ToDataTable(); // 转换成DataTable类型
 table.AddIdentityColumn(); //给DataTable增加一个自增列
 table.HasRows(); // 检查DataTable 是否有数据行
 table.ToList<T>(); // datatable转List
+var set = list.ToHashSet(s=>s.Name);// 转HashSet
 ```
 ### 40.Mime类型
 ```csharp
@@ -986,6 +987,14 @@ DateTime.Now.GetTotalSeconds(); // 获取该时间相对于1970-01-01 00:00:00
 DateTime.Now.GetTotalMilliseconds(); // 获取该时间相对于1970-01-01 00:00:00的毫秒数
 DateTime.Now.GetTotalMicroseconds(); // 获取该时间相对于1970-01-01 00:00:00的微秒数
 DateTime.Now.GetTotalNanoseconds(); // 获取该时间相对于1970-01-01 00:00:00的纳秒数
+var indate=DateTime.Parse("2020-8-3").In(DateTime.Parse("2020-8-2"),DateTime.Parse("2020-8-4"));//true
+
+//时间段计算工具
+var range = new DateTimeRange(DateTime.Parse("2020-8-3"), DateTime.Parse("2020-8-5"));
+range.Union(DateTime.Parse("2020-8-4"), DateTime.Parse("2020-8-6")); //连接两个时间段，结果：2020-8-3~2020-8-6
+range.In(DateTime.Parse("2020-8-3"), DateTime.Parse("2020-8-6"));//判断是否在某个时间段内，true
+var (intersected,range2) = range.Intersect(DateTime.Parse("2020-8-4"), DateTime.Parse("2020-8-6"));//两个时间段是否相交，(true,2020-8-3~2020-8-4)
+range.Contains(DateTime.Parse("2020-8-3"), DateTime.Parse("2020-8-4"));//判断是否包含某个时间段，true
 ...
 ```
 ### 42.流转换