c# - How to identify only change rows in datagrid which is bind ObservableCollection in WPF MVVM -

i have data grid bind observable collection. first load data database. if change 1 row , click on save button should update particular row. if add new rows, when click save id should insert rows database. don't have doubt update , insert database. problem how identify row changes.

<datagrid selectedindex="{binding selectedintex}" isenabled="{binding iskeyset}" canuserdeleterows="false" canuseraddrows="false" name="dgwtemplatedetails" selectionmode="single" itemssource="{binding ordertemplatelist, mode=twoway}" selecteditem="{binding selectedordertemplate}" isreadonly="false" autogeneratecolumns="false" width="auto">                      <datagrid.columns>                          <datagridtextcolumn header="change state" visibility="visible" binding="{binding changestate}"/>                          <datagridtextcolumn header="srl no" visibility="hidden" binding="{binding srlno}"/>                          <datagridtextcolumn header="act code" width="75" binding="{binding actcode}"/>                          <datagridtextcolumn header="act name" width="275" binding="{binding actname}"/>                          <datagridtextcolumn header="no. of days" width="75" binding="{binding noofdays}"/>                          <datagridcheckboxcolumn header="is cutting" width="75" binding="{binding iscutselected}" />                        </datagrid.columns>                  </datagrid>

as far aware, there no way identify this. can add property in class called haschanged

public bool haschanged { get; set; } 

and in setter code of of other properties, set haschanged property true. example:

private string _actname;  public string actname  {       {       return _actname;    }    set    {       _actname = value;       this.haschanged = true;        //inotifypropertychanged stuff if using here.    } } 

when save changes database, can select of records has changed property set true.

var haschanged = ordertemplatelist.where(x => x.haschanged);