解决导入时间不填写时转换报错的问题

be/Modules/Shared/src/Win_in.Sfs.Shared.Application/ExportAndImport/ClosedXmlExportImportService.cs

@@ -186,12 +186,15 @@ public class ClosedXmlExportImportService : IExportImportService
                             }
                         }
                         else
+                        {
+                            if (value.ToString() != "")
                             {
                                 var propertyValue = Convert.ChangeType(value.ToString(), propertyType);
                                 property.SetValue(model, propertyValue);
                             }
                         }
                     }
+                }
                 result.Add(model);
             }
             //