为什么这个未定义，我该如何解决这个问题？ C＃

Question

我创建了一个场景，我需要3个单选按钮来处理多个问题。我在单选按钮上添加了值，我想将所选单选按钮的总点数相加，并将其显示在文本框中。

这是我的代码，我在试图弄清楚为什么我收到未定义的错误消息时遇到了困难。

 function getSelectionPoints(selection) {
        return parseInt(selection.split(",")[1]);
    }

    function getSelectionObj(selectionID) {
        var selection = null;

        if(selectionID == 1)
            selection = document.getElementById("<%=selection1.ClientID %>").getElementsByTagName("input");
        else if (selectionID == 2)
            selection = document.getElementById("<%=selection2.ClientID %>").getElementsByTagName("input");
        else if (selectionID == 3)
            selection = document.getElementById("<%=selection3.ClientID %>").getElementsByTagName("input");

        return selection;
    }

    function getTotalPoints() {
        var totalPoints = 0;
        var selection;
        var promotionDropdown = document.getElementById("<%=dropDownPromotionTo.ClientID %>");
        var promotionFromID = parseInt(document.getElementById("<%=promotionIDFromHidden.ClientID %>").value);
        var promotionToID = parseInt(promotionDropdown.options[promotionDropdown.selectedIndex].value);

        for (var i = 1; i <= 9; i++) {
            selection = getSelectionObj(i);

            if (i == 9 && (promotionFromID == 2 || promotionFromID == 3 || promotionToID == 2 || promotionToID == 3)) {
                totalPoints += 0;
            }

            else if (selection != null) {
                for (var j = 0; j < selection.length; j++) {
                    if (selection[j].checked) {
                        totalPoints += getSelectionPoints(selection[j].value);
                        break;
                    }
                }
            }
        }
        alert(totalpoints); 
        return totalPoints;
    }
    <asp:RadioButtonList ID="selection1" runat="server"
                    EnableTheming="True" SkinID="Black" CausesValidation="True" onchange="updateMyPoints(false, true);">
                        <asp:ListItem Value="1,6">Spectacular</asp:ListItem>
                        <asp:ListItem Value="2,4" Selected="True">Average</asp:ListItem>
                        <asp:ListItem Value="3,0">Needs improvement</asp:ListItem>
                    </asp:RadioButtonList>

Answer 1

JavaScript区分大小写，请使用totalPoints代替totalpoints：

alert(totalPoints);