c# word转换HTML后 HTML编码是charset=x-cp20936怎么转换成UTF-8

怎么利用Microsoft.Office.Interop.Word.Document 中的
SaveAs(ref Target, ref format,

ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown,

ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown, ref Unknown);
方法转成UTF-8 其中第12个参数是[In, Optional] ref object Encoding,

https://msdn.microsoft.com/en-us/library/microsoft.office.interop.word._document.saveas(v=office.11).ASPX

var fix = function (selector) {

$(selector + ' :input[placeholder]').each(function (index, element) {
var self = $(this);
if (self.attr('fix-placeholder') !== undefined) {
setTimeout(function () {
var holder = self.prev("label");
if ($.trim(self.val()).length > 0) {
holder.hide();

同问。。。