Web Forms :: Load Gridview Row With Data From Dataset

I have a gridview to which i am adding rows dynamically at the click event of a button placed in gridview footer template. When i want to update data. I have to load the gridview with all the rows required. I get the sql table data in the dataset object and then i have to load this in the gridview. How can i do this? Only one row gets loaded when i use this code: 

DataSet DSContact = DMLObj.Load_DataSet("Usp_LoadData", "ContactPerson", idf);  foreach (GridViewRow row in GVContactPerson.Rows)  {    ((TextBox)row.FindControl("txtContactName")).Text=DSContact.Tables[0].Rows[0]["ContactName"].ToString();  ((TextBox)row.FindControl("txtemail")).Text = DSContact.Tables[0].Rows[0]["ContactEmailID"].ToString();  ((TextBox)row.FindControl("txtmob1")).Text = DSContact.Tables[0].Rows[0]["ContactMobile"].ToString();  Session["contact"] = ((TextBox)row.FindControl("txtContactName")).Text;  string pid = Convert.ToString(DMLObj.getid("Select ContactPersonID from tbl_ContactPersonDetails where ContactName='" + Session["contact"].ToString() + "'"));  Session["contactID"] = pid;  }