From 4ec638670af613bd2f33988b4d3897a2e551f506 Mon Sep 17 00:00:00 2001
From: 28810 <28810@YEXIANGQIN>
Date: Sun, 24 May 2020 02:53:36 +0800
Subject: [PATCH] update

---
 更新日志.md   |  1 +
 表达式函数.md | 43 +++++++++++++++++++++++++++++--------------
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/更新日志.md b/更新日志.md
index 06b8c2c..3e8a2e1 100644
--- a/更新日志.md
+++ b/更新日志.md
@@ -12,6 +12,7 @@
 - 修复 Enum 类型无元素时的错误；
 - **增加 IFreeSql.InsertOrUpdate 方法 [wiki](https://github.com/dotnetcore/FreeSql/wiki/%E6%B7%BB%E5%8A%A0%E6%88%96%E4%BF%AE%E6%94%B9)；**
 - **增加 ISelect.WhereDynamicFilter 方法实现动态过滤条件（与前端交互）[wiki](https://github.com/dotnetcore/FreeSql/wiki/%E6%9F%A5%E8%AF%A2)；**
+- **增加 MySql/SqlServer 表达式解析 yyyyMMdd 常用 c# 日期格式化；**
 - 增加 WhereCascade/GlobalFilter 表达式子查询的支持；
 - 增加 \[Description\] 元数据注释，优先级低于 c# 代码注释；
 - 增加 IUpdate.SetIf 方法；
diff --git a/表达式函数.md b/表达式函数.md
index 5076929..d6f80c3 100644
--- a/表达式函数.md
+++ b/表达式函数.md
@@ -51,6 +51,7 @@ var list2 = fsql.Select<T>()
 ```
 
 ## Exists子表
+
 ```csharp
 var list2 = fsql.Select<T>()
   .Where(a => fsql.Select<T>()
@@ -79,6 +80,20 @@ var t4 = fsql.Select<T>()
 
 > SqlServer nvarchar/varchar 已兼容表达式解析，分别解析为：N'' 和 ''，优化索引执行计划；
 
+## 日期格式化
+
+```csharp
+var t4 = fsql.Select<T>()
+  .First(a => a.CreateTime.ToString("HH:mm:ss");
+// SELECT date_format(a.`CreateTime`, '%H:%i:%s') as1 
+// FROM `xxx` a 
+// limit 0,1
+```
+
+> v1.5.0 支持了常用 c# 日期格式化，yyyy MM dd HH mm ss yy M d H hh h m s tt t
+
+> tt t 为 AM PM
+
 ## 自定义解析
 
 ```csharp
@@ -122,8 +137,8 @@ var sql1 = fsql.Select<SysModule>()
 
 ```csharp
 var fsql = new FreeSqlBuilder() //请务必定义成 Singleton 单例模式
-    .UseGenerateCommandParameterWithLambda(true)
-    ...
+  .UseGenerateCommandParameterWithLambda(true)
+  ...
 
 var id = 1;
 fsql.Select<Song>().Where(a => a.Id == id).ToList();
@@ -139,28 +154,28 @@ fsql.Select<Song>().Where(a => a.Id == id).ToList();
 ```csharp
 var name = "testname";
 fsql.Select<TestMySqlStringIsNullable>()
-    .Where(a => a.varchar == name).ToList();
+  .Where(a => a.varchar == name).ToList();
 
 fsql.Select<TestMySqlStringIsNullable>()
-    .Where(a => a.varchar == name.SetDbParameter(10)).ToList();
+  .Where(a => a.varchar == name.SetDbParameter(10)).ToList();
 
 public class TestMySqlStringIsNullable {
-    public Guid id { get; set; }
+  public Guid id { get; set; }
 
-    [Column(DbType = "varchar(100)")]
-    public string varchar { get; set; }
+  [Column(DbType = "varchar(100)")]
+  public string varchar { get; set; }
 }
 
 [ExpressionCall]
 public static class DbFunc {
-    static ThreadLocal<ExpressionCallContext> context = new ThreadLocal<ExpressionCallContext>();
+  static ThreadLocal<ExpressionCallContext> context = new ThreadLocal<ExpressionCallContext>();
 
-    public static string SetDbParameter(this string that, int size)
-    {
-        if (context.Value.DbParameter != null)
-            context.Value.DbParameter.Size = size;
-        return context.Value.ParsedContent["that"];
-    }
+  public static string SetDbParameter(this string that, int size)
+  {
+    if (context.Value.DbParameter != null)
+      context.Value.DbParameter.Size = size;
+    return context.Value.ParsedContent["that"];
+  }
 }
 ```