cell single clik for data grid wpf

I have binded data table to data grid
one coloumn is of type checkbox ie boo,l in data table.

Now at check of a checkbox( cell containing check box) I need to save data table changes to file.

How I can achieve this is there any solution? 

I have  tried by adding data template at auto genarting coloum.

<DataTemplate x:Key="cellCheckbox"><CheckBox Checked="CheckBox_Checked_1" Unchecked="CheckBox_Unchecked_1"></CheckBox></DataTemplate>

if (e.PropertyName == modelName)
            {
                DataTemplate checkBoxTemplate = new DataTemplate();
                checkBoxTemplate = (DataTemplate)Resources["cellCheckbox"];
                DataGridTemplateColumn templateColumn = new DataGridTemplateColumn();
                templateColumn.CellTemplate = checkBoxTemplate;
            }