DocumentDirectories.cs

// For complete examples and data files, please go to https://github.com/groupdocsassembly/GroupDocs_Assembly_NET
/// <summary>
/// Takes source file name as argument. 
/// </summary>
/// <param name="sourceFileName">Source file name</param>
/// <returns>Returns explicit path by combining source folder path and source file name.</returns>
public static string GetSourceDocument(string sourceFileName)
{
    return Path.Combine(Path.GetFullPath(sourceFolderPath), sourceFileName);
}
/// <summary>
/// Takes output file name as argument. 
/// </summary>
/// <param name="outputFileName">output file name</param>
/// <returns>Returns explicit path by combining destination folder path and output file name.</returns>

public static string SetDestinationDocument(string outputFileName)
{
    return Path.Combine(Path.GetFullPath(destinationFolderPath), outputFileName);
}