There are two ways of DataReader binding DataGridView

First: With the help of BindingSource
SqlDataReader sdr= The SqlDataReader type of data obtained by the query function;
BindingSource bs=new BindingSource ();
BS.DATASOURCE=SDR;
Datagridview.datasource=bs;

second: with DATATABLE
datatable dt=new DataTable ();
dt.load (SDR);
datagridview.datasource=bs;

get DataGridView of the selected row
string num=convert.tostring (Datagridview[0, DataGridView.CurrentCell.RowIndex]. Value);
The first column of the selected row is converted to a string type of data that can be manipulated through SQL statements.