support for enum type of db /支持 数据库 enum

Author: [email protected]

Dapper/Dapper.csproj

@@ -6,6 +6,7 @@
     <Description>A high performance Micro-ORM supporting SQL Server, MySQL, Sqlite, SqlCE, Firebird etc..</Description>
     <Authors>Sam Saffron;Marc Gravell;Nick Craver</Authors>
     <TargetFrameworks>net461;netstandard2.0;net5.0</TargetFrameworks>
+    <GeneratePackageOnBuild>true</GeneratePackageOnBuild>
   </PropertyGroup>
   <ItemGroup>
     <Folder Include="Properties\" />

Dapper/SqlMapper.cs

@@ -367,7 +367,7 @@ public static void SetDbType(IDataParameter parameter, object value)
             handler = null;
             var nullUnderlyingType = Nullable.GetUnderlyingType(type);
             if (nullUnderlyingType != null) type = nullUnderlyingType;
-            if (type.IsEnum && !typeMap.ContainsKey(type))
+            if (type.IsEnum && !typeMap.ContainsKey(type) && !typeHandlers.ContainsKey(type))
             {
                 type = Enum.GetUnderlyingType(type);
             }