Try this..:)
protected void button_Click(object s, EventArg e)
{
foreach (GridViewRow row in gvExportCourse.Rows)
{
Label exCourse = (Label)row.FindControl("gvlblCourseName");
Label exUniversityCourse = (Label)row.FindControl("gvlblUniversityCourseName");
}
label1.Text = "Course saved successfully.";
}