Make a data grid view row selected on Treeview selection

1) you need to map the nodes to corresponding datagrid rows

this.dataGridView1.Rows[0].Tag = id; // a node id 

2) handle node click event and find corresponding row by id and select it

if (tvwACH.SelectedNode.Parent != null) {         int id  = (int)tvwACH.SelectedNode.Tag ; // make sure you've already assigned tag when creating Three nodes and data rows         foreach(DataGridViewRow  row in this.dataGridView1.Rows)         {            int rowId = (int)row.Tag ;             if(rowId == id)             {               row.Selected = ture;             }             else             {               row.Selected = false; //discard other rows              }           } }

For Reference check this link
http://stackoverflow.com/questions/4343897/is-it-possible-to-select-both-treeview-node-and-the-row-of-a-datagridview

http://www.codeproject.com/Answers/108651/How-to-make-the-particular-row-get-selected-in-dat.aspx#answer1