“ProjectClient”名称在当前上下文中不存在

Question

我正在尝试在沙盒解决方案中创建可视webpart。我在ascx页面中添加了一个名为ProjectClient的下拉列表，并编写了一个函数来绑定代码隐藏中的下拉列表。但我得到的错误是“名称'ProjectClient'在当前上下文中不存在”。我检查了ascx.g.cs页面，控件ID在那里是正确的。请帮我解决这个问题。

ascx页面：

<div class="col-lg-1">
                                        <asp:Label ID="pClient" runat="server" Text='<%#Eval("Client") %>' />
                                        <asp:DropDownList ID="ProjectClient" runat="server" CssClass="ddclient" Visible="false"></asp:DropDownList>
                                    </div>

文件后面的代码：

 public void BindDropDown()
        {
            ProjectClient.Items.Clear();
            if (listToBind != null)
            {
                ProjectClient.DataSource = listToBind;
                ProjectClient.DataTextField = textField;
                ProjectClient.DataValueField = valueField;
                ProjectClient.DataBind();
            }
           ProjectClient.Items.Insert(0, new ListItem("-Select-", ""));
        }

ascx.g.cs页面：

[global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Never)]
        [GeneratedCodeAttribute("Microsoft.VisualStudio.SharePoint.ProjectExtensions.CodeGenerators.SharePointWebP" +
            "artCodeGenerator", "12.0.0.0")]
        private global::System.Web.UI.WebControls.DropDownList @__BuildControl__control7() {
            global::System.Web.UI.WebControls.DropDownList @__ctrl;
            @__ctrl = new global::System.Web.UI.WebControls.DropDownList();
            @__ctrl.TemplateControl = this;
            @__ctrl.ApplyStyleSheetSkin(this.Page);
            @__ctrl.ID = "ProjectClient";
            @__ctrl.CssClass = "ddclient";
            @__ctrl.Visible = false;
            return @__ctrl;
        }