Creating XML file with write access given to all the windows account users

I am creating an XML file in the common application folder using C#:

%ALLUSERSPROFILE%\Application Data\

File will 开发者_StackOverflowbe created when application is installed. This file is something that is common to all the users of the local machine.(i.e it contains some setting information)

But my problem is when the file is created by an admin user(i.e application is installed by an admin user) the other users don't have write access to the file. When I checked the attributes of the file, it has given only 'read and execute' is given to other users.

I am using below code to save the file

XDocument.Save(filePath);

Is it possible to create file with write access given to all users? Any help much appreciated!

You can't pass information about ACL into XDocument.Save method, but you can modify permissions of file after saving your xml document. You can use the following code to perform it (don't forget to add reference to System.Security.dll):

using System.Security.AccessControl;
using System.Security.Principal;
using System.IO;

public class FileAccessRulesHelper
{
    public void AddWriteRightsToEveryone(string filename)
    {
        // get sid of everyone group
        SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.WorldSid, null);
        // create rule
        FileSystemAccessRule rule = new FileSystemAccessRule(sid, FileSystemRights.Write, AccessControlType.Allow);
        // get ACL of file
        FileSecurity fsecurity = File.GetAccessControl(filename);
        // modify ACL of file
        fsecurity.AddAccessRule(rule);
        // apply modified ACL to file
        File.SetAccessControl(filename, fsecurity);
    }
}

I don't think you can pass a parameter to XDocument.Save to control the permissions but you should be able to set them after the save. Something like the following should do:

System.Security.AccessControl.FileSecurity fsec = System.IO.File.GetAccessControl(fileName);
fsec.AddAccessRule( new System.Security.AccessControl.FileSystemAccessRule("Everyone", System.Security.AccessControl.FileSystemRights.Modify, System.Security.AccessControl.AccessControlType.Allow));
System.IO.File.SetAccessControl(fileName, fsec);

I had a similar problem with a service install. You can use the following code to give a folder different permissions.

public static void CreateWithFullAccess(string targetDirectory)
    {
        try
        {
            if (!Directory.Exists(targetDirectory))
            {
                Directory.CreateDirectory(targetDirectory);
            }
            DirectoryInfo info = new DirectoryInfo(targetDirectory);
            SecurityIdentifier allUsersSid =
            new SecurityIdentifier(WellKnownSidType.LocalServiceSid,
            null);
            DirectorySecurity security = info.GetAccessControl();
            security.AddAccessRule(
            new FileSystemAccessRule(allUsersSid,
            FileSystemRights.FullControl,
            AccessControlType.Allow));
            info.SetAccessControl(security);
        }
        catch (Exception ex)
        {
            System.Windows.Forms.MessageBox.Show(ex.ToString());
        }
    }