Export Repeater / GridView with Chinese (Mandarin) Character to Excel in ASP.Net

Here I have created sample that full-fill your requirement.

HTML

<div>
    <div>
        <asp:Repeater ID="comments" runat="server">
            <HeaderTemplate>
                <table>
                    <tr>
                        <th>
                            Descript
                        </th>
                    </tr>
                </table>
            </HeaderTemplate>
            <ItemTemplate>
                <table>
                    <tr>
                        <td>
                            <%#DataBinder.Eval(Container.DataItem, "descript_computed")%>
                        </td>
                    </tr>
                </table>
            </ItemTemplate>
            <AlternatingItemTemplate>
                <table>
                    <tr>
                        <td>
                            <%#DataBinder.Eval(Container.DataItem, "descript_computed")%>
                        </td>
                    </tr>
                </table>
            </AlternatingItemTemplate>
            <FooterTemplate>
            </FooterTemplate>
        </asp:Repeater>
    </div>
    <br />
    <br />
    <asp:Button Text="Export" OnClick="ExportToExcel" runat="server" />
</div>

Code

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[1] { new DataColumn("descript_computed", typeof(string)) });
        dt.Rows.Add("脚宽");
        dt.Rows.Add("膝盖围");
        dt.Rows.Add("袖笼弯量");
        dt.Rows.Add("袖笼直量");
        dt.Rows.Add("肩缝向前倾");
        dt.Rows.Add("肩斜");
        dt.Rows.Add("肩宽");
        dt.Rows.Add("胸围-腋下1“");
        dt.Rows.Add("腰围-肩点下16”");
        dt.Rows.Add("下摆宽");
        dt.Rows.Add("下摆折边高");
        dt.Rows.Add("前身长-肩点下");
        dt.Rows.Add("后中长");
        dt.Rows.Add("请简单介绍");
        comments.DataSource = dt;
        comments.DataBind();
    }
}

protected void ExportToExcel(object sender, EventArgs e)
{
    Response.Clear();
    Response.ClearContent();
    Response.ClearHeaders();
    Response.Charset = "utf-8";
    Response.AddHeader("content-disposition", "attachment; filename=FileName.xls");
    Response.ContentEncoding = System.Text.Encoding.Unicode;
    Response.ContentType = "application/ms-excel";
    Response.BinaryWrite(System.Text.Encoding.Unicode.GetPreamble());
    StringWriter sw = new StringWriter();
    HtmlTextWriter hw = new HtmlTextWriter(sw);
    comments.RenderControl(hw);
    Response.Output.Write(sw.ToString());
    Response.Flush();
    Response.End();       
}

Screenshot

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