如何在C#中访问已打开的Excel文件？

Question

我在Windows资源管理器中双击打开了excel工作簿,但无法在代码中访问它

Excel.Application xlApp = (Application)Marshal.GetActiveObject("Excel.Application");
Excel.Workbooks xlBooks = xlApp.Workbooks;

xlBooks.Count等于0,为什么不引用我打开的工作簿？

编辑

以下是各种场景和发生的情况:

场景1:如果文件尚未打开

• 代码打开工作簿,我很高兴.

场景2:如果文件最初是从代码打开的,我关闭并重新打开应用程序

• 代码引用文件就好了xlBooks.Count等于1,我很高兴.

场景3:如果文件最初不是从代码打开,而是通过在资源管理器中双击它

• 代码打开文件的另一个实例xlBooks.Count等于0,我很愤怒!

这是现在的整个代码

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using Microsoft.Office.Interop.Excel;

public class ExcelService : IExcelService
{
    const string _filePath = @"C:\Somewhere";
    const string _fileName = @"TestFile.xlsb";
    string _fileNameAndPath = Path.Combine(_filePath, _fileName);

    Application xlApp;
    Workbooks xlBooks;
    Workbook xlBook;
    Worksheet xlSheet;

    public ExcelService()
    {
        try
        {
            xlApp = (Application)Marshal.GetActiveObject("Excel.Application");
            xlBooks = xlApp.Workbooks;

            var numBooks = xlBooks.Count;
            Log.Info("Number of workbooks: {0}".FormatWith(numBooks));
            if (numBooks > 0)
            {
                xlBook = xlBooks[1];
                Log.Info("Using already opened workbook");
            }
            else
            {
                xlBook = xlBooks.Open(_fileNameAndPath);
                Log.Info("Opening workbook: {0}".FormatWith(_fileNameAndPath));
            }

            xlSheet = (Worksheet)xlBook.Worksheets[1];

            // test reading a named range
            string value = xlSheet.Range["TEST"].Value.ToString();
            Log.Info(@"TEST: {0}".FormatWith(value));

            xlApp.Visible = true;
        }
        catch (Exception e)
        {
            Log.Error(e.Message);
        }
    }

    ~ExcelService()
    {
        GC.Collect();
        GC.WaitForPendingFinalizers();

        try
        {
            Marshal.FinalReleaseComObject(xlSheet);
        }
        catch { }

        try
        {
            Marshal.FinalReleaseComObject(xlBook);
        }
        catch { }

        try
        {
            Marshal.FinalReleaseComObject(xlBooks);
        }
        catch { }

        try
        {
            Marshal.FinalReleaseComObject(xlApp);
        }
        catch { }
    }
}

Answer 1

我知道这个帖子有点旧,但我找到了另一种方法.创建新Excel.Application对象时,必须创建WorkBooks对象.当您访问已打开的Excel文件时,该WorkBooks对象已经创建,因此您只需要将新的WorkBook添加到现有的WorkBook中.如果您可以访问WorkBook名称,@ Tipx的解决方案很有用,但在我的情况下,当前的WorkBook名称始终是随机的.这是我想出来解决这个问题的解决方案:

Excel.Application excelApp = null;
Excel.Workbooks wkbks = null;
Excel.Workbook wkbk = null;

bool wasFoundRunning = false;

Excel.Application tApp = null;
//Checks to see if excel is opened
try
{
    tApp = (Excel.Application)System.Runtime.InteropServices.Marshal.GetActiveObject("Excel.Application");
    wasFoundRunning = true;
}
catch (Exception)//Excel not open
{
    wasFoundRunning = false;
}
finally
{
    if (true == wasFoundRunning)
    {
        excelApp = tApp;
        wkbk = excelApp.Workbooks.Add(Type.Missing);                    
    }
    else
    {
        excelApp = new Excel.Application();
        wkbks = excelApp.Workbooks;
        wkbk = wkbks.Add(Type.Missing);
    }
    //Release the temp if in use
    if (null != tApp) { Marshal.FinalReleaseComObject(tApp); }
    tApp = null;
}
//Initialize the sheets in the new workbook

可能不是最好的解决方案,但它符合我的需求.希望这有助于某人.:)

Answer 2

如果您的所有工作簿都在同一个 Excel 实例中打开（您可以通过检查是否可以使用 Alt-tab 从一个工作簿切换到另一个工作簿来检查这一点）。您可以简单地使用 来参考其他内容Workbooks("[FileName]")。因此，例如：

Dim wb as Workbook //for C#, type Excel.Workbook wb = null;
Set wb = Workbooks("MyDuperWorkbook.xlsx") //for C#, type wb = Excel.Workbooks["MyDuperWorkbook.xlsx"];
wb.Sheets(1).Cells(1,1).Value = "Wahou!"