Cacher is the code snippet organizer for pro developers

//For complete examples and data files, please go to https://github.com/groupdocsmetadata/GroupDocs_Metadata_NET
public class DocCleaner
{
    // Absolute path to the GroupDocs.Metadata license file
    private const string LicensePath = @"GroupDocs.Metadata.lic";

    // Absolute path to the documents directory
    public string DocumentsPath { get; set; }

    static DocCleaner()
    {
        /* set product license 
         * uncomment following function if you have product license
         * */
        //SetInternalLicense();
    }

    public DocCleaner(string documentsPath)
    {
        // check if directory exists
        if (!Directory.Exists(Common.MapSourceFilePath( documentsPath)))
        {
            throw new DirectoryNotFoundException("Directory not found: " + documentsPath);
        }

        this.DocumentsPath = documentsPath;
    }
    /// <summary>
    /// Applies the product license
    /// </summary>
    private static void SetInternalLicense()
    { 
        License license = new License();
        license.SetLicense(LicensePath);
    }

    /// <summary>
    /// Takes author name and removes metadata in files created by specified author
    /// </summary>
    /// <param name="authorName">Author name</param>
    public void RemoveMetadataByAuthor(string authorName)
    {
        // Map directory in source folder
        string sourceDirectoryPath = Common.MapSourceFilePath(this.DocumentsPath);
        
        // get files presented in target directory
        string[] files = Directory.GetFiles(sourceDirectoryPath);

        foreach (string path in files)
        {
            // recognize format
            FormatBase format = FormatFactory.RecognizeFormat(path);
            
            // initialize DocFormat
            DocFormat docFormat = format as DocFormat;
            if (docFormat != null)
            {
                // get document properties
                DocMetadata properties = docFormat.DocumentProperties;

                // check if author is the same
                if (string.Equals(properties.Author, authorName, StringComparison.OrdinalIgnoreCase))
                {
                    // remove comments
                    docFormat.ClearComments();

                    List<string> customKeys = new List<string>();

                    // find all custom keys
                    foreach (KeyValuePair<string, PropertyValue> keyValuePair in properties)
                    {
                        if (!properties.IsBuiltIn(keyValuePair.Key))
                        {
                            customKeys.Add(keyValuePair.Key);
                        }
                    }

                    // and remove all of them
                    foreach (string key in customKeys)
                    {
                        properties.Remove(key);
                    }
                    //====== yet to change things =========================
                    // and commit changes
                    string fileName = Path.GetFileName(path);
                    string outputFilePath = Common.MapDestinationFilePath(this.DocumentsPath + "/" + fileName);
                    docFormat.Save(outputFilePath);
                    //=====================================================
                }
            }
        }

        Console.WriteLine("Press any key to exit.");
    }
}