/// <summary>
        /// PDF另存為效果
        /// </summary>
        /// <param name="fileName">PDF文件名</param>
        /// <param name="saveFileName">另存結果文件名</param>
        public static void PDFSaveAs(String fileName, string saveFileName)
        {
            Acrobat.CAcroPDDoc pdfDoc = null;
            pdfDoc = (Acrobat.CAcroPDDoc)Microsoft.VisualBasic.Interaction.CreateObject("AcroExch.PDDoc", "");
            if (!pdfDoc.Open(fileName)) { string.Format("源文件{0}不存在！", fileName); }

            Object jsObj = pdfDoc.GetJSObject();
            Type T = jsObj.GetType();

            object[] saveAsParam = { saveFileName, "com.adobe.acrobat.tiff" }; //com.adobe.acrobat.tiff 表示TIFF文件
            T.InvokeMember(
                "saveAs",
                BindingFlags.InvokeMethod |
                BindingFlags.Public |
                BindingFlags.Instance,
                null, jsObj, saveAsParam);
            pdfDoc.Close();
        }