ASP.NET:以编程方式设置HTML元素的样式

Question

我正在生成一个菜单,其中一个Repeater控件绑定到一个XmlDataSource.

<asp:Repeater ID="myRepeater" runat="server" 
    DataSourceID="myDataSource" 
    onitemdatabound="myRepeater_ItemDataBound" 
    onitemcreated="myRepeater_ItemCreated">
    <HeaderTemplate>
        <ul class="menu_list">
    </HeaderTemplate>
    <ItemTemplate>
        <li id="liMenu" runat="server"><asp:HyperLink ID="hrefMenuItem" runat="server" Text='<%# XPath("@text")%>' NavigateUrl='<%# XPath("@href")%>'></asp:HyperLink></li>
    </ItemTemplate>
    <FooterTemplate>
        </ul>
    </FooterTemplate>
</asp:Repeater>
<asp:XmlDataSource runat="server" ID ="myDataSource" XPath="Menu/Items/*" EnableCaching="False" /> 

我希望能够根据鼠标悬停事件和当前选择的菜单项设置包含LI的样式.我尝试通过HtmlGenericControl,但我收到一个错误,它是readonly.

protected void myRepeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
        {
            if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
            {
                HyperLink hrefCurrentMenuLink = e.Item.FindControl("hrefMenuItem") as HyperLink;
                HtmlGenericControl l_genericControl = e.Item.FindControl("liMenu") as HtmlGenericControl;

                if ((hrefCurrentMenuLink != null) && (l_genericControl != null))
                {
                    string l_currentPage = GetCurrentWebPage();

                    if (String.Compare(Path.GetFileNameWithoutExtension(hrefCurrentMenuLink.NavigateUrl), l_currentPage, StringComparison.OrdinalIgnoreCase) == 0)
                        l_genericControl.Style = "on-nav";
                    else
                        l_genericControl.Style = "off-nav";

                    l_genericControl.Attributes.Add("onmouseover", "navOn(this)");
                    l_genericControl.Attributes.Add("onmouseout", "navOff(this)");
                }
            }
        }

有没有办法实现这个目标？

Answer 1

style属性是一个集合.做这个:

l_genericControl.Style.Add("css-name", "css-value")

或者,如果您使用的是CSS类,则更改CssClass属性:

l_genericControl.CssClass = "on-nav";

如果您尝试使用javascript切换CSS类,请尝试这样的(未经测试):

l_genericControl.Attributes.Add("onmouseover", "this.className='on-nav';");
l_genericControl.Attributes.Add("onmouseout", "this.className='off-nav';");

如果你想用你的javascript更改样式,这可能有效:

l_genericControl.Attributes.Add("onmouseover", "this.style.color='red'; this.style.backgroundColor='yellow';");
l_genericControl.Attributes.Add("onmouseout", "this.style.color='black'; this.style.backgroundColor='none';");