Visual Studio Express (Visual Basic) 中的 Excel.Application 错误

Question

使用 Excel 2010、Visual Studio Express 2013。

我在 Visual Studio for Microsoft Excel 14.0 中添加了引用对象库

Imports Microsoft.Office.Core
Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        Dim oXL As Excel.Application
        Dim oWB As Excel.Workbook
        Dim oSheet As Excel.Worksheet
        Dim oRng As Excel.Range

        ' Start Excel and get Application object.
        oXL = CreateObject("Excel.Application")
        oXL.Visible = True
    End Sub
End Class

但是它给了我以下错误：

类型“Excel.Application”未定义。
类型“Excel.Workbook”未定义。
类型“Excel.Worksheet”未定义。
类型“Excel.Range”未定义。

如果我在 Excel 版本中使用了错误的参考库，请说明如何将正确的对象库添加到列表中。

Answer 1

您导入了错误的命名空间。

改变

Imports Microsoft.Office.Core

到

Imports Microsoft.Office.Interop

如果您尚未添加对 Microsoft Excel 15.0 对象库的引用（将 15.0 替换为您的版本）

您可以使用正确的类型来代替后期绑定

' using the fully-qualified class name as an example.
' Excel.Application would work just fine because Microsoft.Office.Interop is imported
Dim oXL As Microsoft.Office.Interop.Excel.Application
Dim oWB As Excel.Workbook
Dim oSheet As Excel.Worksheet
Dim oRng As Excel.Range

' Start Excel and get Application object.
oXL = New Excel.Application()
' note that you have proper intellisense now because oXl is no longer just an Object.
oXl.Visible = True

最后，要正确清理您的 Excel 引用，因为它是一个 COM 对象，请将其放在您完成对象的代码中（例如，在关闭表单时）。为您创建的每个 COM 对象执行此操作。

System.Runtime.InteropServices.Marshal.ReleaseComObject(oRng)
System.Runtime.InteropServices.Marshal.ReleaseComObject(oSheet)
System.Runtime.InteropServices.Marshal.ReleaseComObject(oWB)
System.Runtime.InteropServices.Marshal.ReleaseComObject(oXL)

Answer 2

想通了。之前的代码来自https://support.microsoft.com/en-us/kb/301982。但是，当我以以下方式编辑代码时，错误消失了。

Imports Microsoft.Office.Core

Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    Dim oXl As Object
    Dim oWB As Object
    'Dim oXL As Excel.Application
    'Dim oWB As Excel.Workbook
    'Dim oSheet As Excel.Worksheet
    'Dim oRng As Excel.Range

    ' Start Excel and get Application object.
    oXL = CreateObject("Excel.Application")
    oXL.Visible = True
End Sub
End Class