protected void btnSubmit_Click(object sender, EventArgs e)
{
string connectionString = ConfigurationManager.ConnectionStrings["connection"].ConnectionString;
_studentService = new Student(connectionString);
_studentService.UpdateStudent(txtName.Text, Convert.ToInt32(txtEnrollNumber.Text), Convert.ToInt32(ddlStreamId.Text), Convert.ToInt32(txtMarks.Text), Convert.ToInt32(ddlStateId.Text), ddlState.Text, ddlStream.Text);
Response.Redirect("HomePage.aspx");
}