private void buttonAdd_Click(object sender, EventArgs e) { if (!CheckInputValue()) { return; } PadInfo newInfo = new PadInfo(); newInfo.Width = landWidth; newInfo.Height = landHeight; newInfo.Shape = shape; int count = listBoxMyStandard.Items.Count; bool existFlag = false; for (int i = 0; i < count; i++) { if (newInfo.Equals((PadInfo)(listBoxMyStandard.Items[i]))) { existFlag = true; break; } } if (existFlag) { return; } int index = listBoxMyStandard.SelectedIndex; if (index < 0) { index = 0; } listBoxMyStandard.Items.Insert(index, newInfo); listBoxMyStandard.SelectedIndex = -1; }