string cs = ConfigurationManager.ConnectionStrings["SS"].ToString();
SqlConnection con = new SqlConnection(cs);
con.Open();
string txtusername = ((TextBox)gvdetails.Rows[e.RowIndex].Cells[3].Controls[0]).Text;
string txtpassword = ((TextBox)gvdetails.Rows[e.RowIndex].Cells[4].Controls[0]).Text;
string txtmobilenumber = ((TextBox)gvdetails.Rows[e.RowIndex].Cells[5].Controls[0]).Text;
string txtemailid = ((TextBox)gvdetails.Rows[e.RowIndex].Cells[6].Controls[0]).Text;
string userid = gvdetails.Rows[e.RowIndex].Cells[2].Text;
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandText = "update userdetails set UserName='" + txtusername + "',Password='" + txtpassword + "',MobileNumber='" + txtmobilenumber + "',EmailId='" + txtemailid + "' where ...
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