我建议首先在解决方案中使用它：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Microsoft.Office.Interop.Word;
 
public partial class Default2 : System.Web.UI.Page
{
    protected void Page_Load(object sender,EventArgs e)
    {
        Microsoft.Office.Interop.Word.Application appWord = new Microsoft.Office.Interop.Word.Application();
        wordDocument = appWord.Documents.Open(@"D:\desktop\xxxxxx.docx");
        wordDocument.ExportAsFixedFormat(@"D:\desktop\DocTo.pdf",WdExportFormat.wdExportFormatPDF);
    }
 
    public Microsoft.Office.Interop.Word.Document wordDocument { get; set; }
}