:zap:代码生成优化

ZR.ServiceCore/Model/Dto/SqlDiffLogDto.cs

@@ -38,10 +38,10 @@ namespace ZR.Model.System.Dto
         public string Sql { get; set; }
 
         [ExcelColumn(Name = "变更前数据", Width = 30)]
-        public string BeforeData { get; set; }
+        public string BeforeData { get; set; } = string.Empty;
 
         [ExcelColumn(Name = "变更后数据", Width = 30)]
-        public string AfterData { get; set; }
+        public string AfterData { get; set; } = string.Empty;
 
         [ExcelColumn(Name = "操作用户名")]
         public string UserName { get; set; }

ZR.ServiceCore/Services/GenTableService.cs

@@ -48,7 +48,7 @@ namespace ZR.ServiceCore.Services
             if (info != null)
             {
                 info.Columns = GenTableColumnService.GenTableColumns(tableId);
-                if (!info.SubTableName.IsEmpty() && info.SubTable != null)
+                if (!info.SubTableName.IsEmpty())
                 {
                     info.SubTable = Queryable().Where(f => f.TableName == info.SubTableName).First();
                     info.SubTable.Columns = GenTableColumnService.GenTableColumns(info.SubTable.TableId);