hi
Try this code...
private void Form1_Load(object sender, EventArgs e)
{
DataTable dt = new DataTable();
dt.Columns.Add("Name", typeof(string));
dt.Columns.Add("address", typeof(string));
dt.Rows.Add("karthik","bangalore");
dt.Rows.Add("parthi", "gujrat");
Dictionary<string, string> dictMapping = new Dictionary<string, string>();
dictMapping.Add("Name", "Name-Modified");
dictMapping.Add("address", "address-Modified");
dataGridView1.DataSource = dt;
foreach (DataGridViewColumn col in dataGridView1.Columns)
{
string colheader = col.HeaderText;
var key = dictMapping.Keys.FirstOrDefault(k => k == colheader);
if (key != null)
col.HeaderText = dictMapping[key];
}
}