How to open an Excel file in C#?

c# .net excel vsto
tksy picture tksy · Jan 21, 2009 · Viewed 326.7k times · Source

I am trying to convert some VBA code to C#. I am new to C#. Currently I am trying to open an Excel file from a folder and if it does not exist then create it. I am trying something like the following. How can I make it work?

Excel.Application objexcel;
Excel.Workbook wbexcel;
bool wbexists;
Excel.Worksheet objsht;
Excel.Range objrange;

objexcel = new Excel.Application();
if (Directory("C:\\csharp\\error report1.xls") = "")
{
    wbexcel.NewSheet();
}

else
{
    wbexcel.Open("C:\\csharp\\error report1.xls");
    objsht = ("sheet1");
}
objsht.Activate();

Answer

abatishchev picture abatishchev · Jan 21, 2009

You need to have installed Microsoft Visual Studio Tools for Office (VSTO).

VSTO can be selected in the Visual Studio installer under Workloads > Web & Cloud > Office/SharePoint Development.

After that create common .NET project and add the reference to Microsoft.Office.Interop.Excel via 'Add Reference... > Assemblies' dialog.

Application excel = new Application();
Workbook wb = excel.Workbooks.Open(path);

Missing.Value is a special reflection struct for unnecessary parameters replacement

In newer versions, the assembly reference required is called Microsoft Excel 16.0 Object Library. If you do not have the latest version installed you might have Microsoft Excel 15.0 Object Library, or an older version, but it is the same process to include.

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