How to check whether a excel file is write protected or not in C#?

I'm developing a sample application in which I have to open an excel file and check whether the file is write protected or not. The code is

using System.Windows.Forms;
using Microsoft.Office.Core;

private void button1_Click(object sender, EventArgs e)
{
    string fileNameAndPath = @"D:\Sample\Sample1.xls"; 
    // the above excel file is a write protected.

    Microsoft.Office.Interop.Excel.Application a = 
              new  Microsoft.Office.Interop.Excel.Application();
    if (System.IO.File.Exists(fileNameAndPath))
    {
        Microsoft.Office.Interop.Excel.ApplicationClass app = 
              new Microsoft.Office.Interop.Excel.ApplicationClass();

        // create the workbook object by opening  the excel file.
        app.Workbooks.Open(fileNameAndPath,0,false,5,"","",true,
                           Microsoft.Office.Interop.Excel.XlPla开发者_开发问答tform.xlWindows,
                           "\t",false, true, 0,false,true,0);

        Microsoft.Office.Interop.Excel._Workbook w = 
              app.Workbooks.Application.ActiveWorkbook;

        if (w.ReadOnly)
              MessageBox.Show("HI");
        // the above condition is true.
    }

}

I would like know whether the file is write protected or not.

You can get the FileAttributes an like this:

if ((File.GetAttributes(fileNameAndPath) & FileAttributes.ReadOnly) > 0)
{
    // The file is read-only (i.e. write-protected)
}

See for documentation: http://msdn.microsoft.com/en-us/library/system.io.fileattributes.aspx

If you want to check if the file is readonly, then you can check using File.GetAttributes(), like this:

if(File.GetAttributes(fileNameAndPath) & FileAttributes.ReadOnly) == FileAttributes.ReadOnly)
{
  //it's readonly :)
}

I think you want to look at the HasPassword property of the WorkBook class.

More info at: http://msdn.microsoft.com/en-us/library/microsoft.office.tools.excel.workbook.haspassword%28VS.80%29.aspx

Edit: Left my old answer below

Do you mean if the file or the workbook is readonly?

To check if the workbook is readonly the WorkBook class has a ReadOnly property.

Otherwise, to check the file, look at using the IO.FileInfo class in the framework to get out the file attributes, like in the following code:

FileInfo fsi = new FileInfo("filepathandname");
if ((fsi.Attributes & FileAttributes.ReadOnly) == FileAttributes.ReadOnly )
{
    // it's readonly
}

You can check File.GetAttributes

Essentially, ReadOnly and Write-protected are the same thing. However, you might be encountering the situation where you are unable to access a file because it is being used by another process. In this case, you try to open it with a FileShare as below:

using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read, 
    FileShare.ReadWrite))
{
    ...
}

You can check protection with

activeDocument.ProtectionType