protected void btnSubmit_Click(object sender, EventArgs e)
{
// Initialize Data
InitData();
GridWorksheet sheet = GridWeb1.WorkSheets["PivotTable Report"];
GridPivotTable pivotTable = sheet.PivotTables[0];
// Sets field item visible property indicating whether the item is visible
pivotTable.Fields("Employee").HideItemByName("David", !CheckBox1.Checked);
pivotTable.Fields("Product").HideItemByName("Maxilaku", !CheckBox2.Checked);
pivotTable.Fields("Continent").HideItemByName("Europe", !CheckBox3.Checked);
pivotTable.Fields("Country").HideItemByName("China", !CheckBox4.Checked);
// Paints PivotTable report
pivotTable.CalculateData();
}