title: Get value from the datagrid after press button/using datagrid selection changed
body: <p>i have a datagrid that load the data from my database. in my datagrid, i also included the , so that i can checked or unchecked the row. </p>
  
  <p>here is the picture.
  <img src="https://i.stack.imgur.com/q1nXb.png" alt="enter image description here"></p>
  
  <p>here is my xaml.</p>
  
  <pre><code>&lt;DataGrid AutoGenerateColumns="False" Height="258" HorizontalAlignment="Left" Margin="12,0,0,12" 
                Name="dataGrid1" VerticalAlignment="Bottom" Width="479" ItemsSource="{Binding data}" 
                AlternatingRowBackground="#FFC4B0B0"&gt;
          &lt;DataGrid.Columns&gt;
              &lt;DataGridTextColumn Binding="{Binding nCateogryID}" Header="No." IsReadOnly="True" Width="30" /&gt;
              &lt;DataGridTextColumn Binding="{Binding sCategoryDesc}" Header="Nama Kategori" IsReadOnly="True" Width="160" /&gt;
              &lt;DataGridTextColumn Binding="{Binding sCategoryItems}" Header="Keterangan Kategori" IsReadOnly="True" Width="170" /&gt;
              &lt;DataGridCheckBoxColumn Header="Checked?" /&gt;
          &lt;/DataGrid.Columns&gt;
      &lt;/DataGrid&gt;
  </code></pre>
  
  <p>May question is:
  How can i know which data already checked whenever i hit the 'Button'? I also do search on google, but found nothing. </p>
  
  <p>i think like this. whenever i click 'Button', i will start to check for each row. how can i do it? any sample for that?</p>
  
  <p>i also think to find another solution, how about using the event handler? thats mean whenever i click for the row and checked, i will trigger the event and check if is it checked or not. How can i do it? </p>
  
  <p>For me, using the event handler is more achieveable because it's much faster rather i have to checked, and press button. lets say if i have only 10 rows, that's not a big problem. How about if i have 1000rows? if i check one by one, it will be troublesome. waste alot of time. any idea? thanks. </p>
  
  <p>Or maybe use the datagrid_selectionchanged.
  How can i check the checkbox has been checked or not? </p>
  
  <p>because if we wait until user press button, then we check is checked or not, i think its a slow process. you have to check for each row. if my row only 10rows, maybe its okay. how about if i have 1000 rows need to check? thanks. :)</p>