正在从复选框中提取文本输出

所以我试图从复选框中提取文本属性，并将其显示到列表框中，但无论是否选中，我做错了什么似乎都无关紧要。

 private void btnCompute_Click(object sender, EventArgs e)
    {
        string accessories = "";
        if (chkChildSeat.Checked) ;
        {
            accessories = accessories + chkChildSeat.Text+",";
        }
        if (chkLockHelmet.Checked) ;
        {
            accessories = accessories + chkLockHelmet.Text+",";
        }
        if (chkTrailer.Checked) ;
        {
            accessories=accessories+chkTrailer.Text;
        }
        lstInvoice.Items.Add(String.Format("{0,-49}{1,-14}", "Invoice Date", DateTime.Now.ToString("d")));
        lstInvoice.Items.Add(String.Format("{0,-50}{1,-13}", Customername, CustomerID));
        lstInvoice.Items.Add(String.Format("{0,-49}{1,-14}", "Rental Date", dateTimePicker1.Value));
        lstInvoice.Items.Add(string.Format("{0,-25}{1,-28}", "Accessories", accessories.ToString()));
        lstInvoice.Items.Add(string.Format("{0,-49}{1,-14}", "Total Invoice Amount", result.ToString("c")));
    }

这将显示所有checkboxname.text属性，无论其是否选中有人能告诉我为什么随着更多选项的选中，列表框上的文本被截断了吗？这与我的字符串格式行有关吗？

lstInvoice.Items.Add(string.Format("{0,-25}{1,-28}", "Accessories", accessories.ToString()));