c# - Ajax ComboBox 正确呈现 ListItems 但不显示

Question

这里ddlSchool是ajax组合框

<code>
ddlSchool.DataSource = dt;
                             ddlSchool.DataTextField = "SchoolName";
                             ddlSchool.DataValueField = "Id";
                             ddlSchool.DataBind();
                             ddlSchool.Items.Insert(0, new System.Web.UI.WebControls.ListItem(" --Select-- ", "0"));
                             ddlSchool.SelectedValue = "0";
</code>

当我检查它呈现值但由于以下原因不显示

<code>
<ul id="ContentPlaceHolder1_ddlSchool_ddlSchool_OptionList" class="ajax__combobox_itemlist" style="visibility: hidden; z-index: 1000; overflow-x: hidden; overflow-y: auto; width: 416px; position: absolute; height: 425px; left: 293px; top: 1458px; display: none;"></ul>
</code>

请帮我获取ListItems

Answer 1

尝试删除:

style="visibility: hidden;display: none;

从样式设置

此外，由于它是绝对位置，它可能会显示在页面上的其他位置，例如不是您期望看到它的位置