How can i find missing bills pdf saved in a folder

Question

Hello experts can you guide how can i find missing or duplicate files in a folder where files are stored as BillNumberxBillSerisxFinYear.pdf 1x10x23.pdf ... 9495x10x23.pdf [ it may have duplicate files 10x10x23(1).pdf, 10x10x23(2).pdf 1x45x23.pdf ... 3000x45x23.pdf

Answer 1

Hi @Sushil Agarwal , Welcome to Microsoft Q&A,

The Regex.IsMatch method is used to match whether the file name matches the pattern of the regular expression ^{expectedFilename}(\d+)$, which means that the file name starts with expectedFilename, followed by a number in parentheses, and then the file extension. . If a file name matches this pattern, it is marked as a duplicate file.

I test smaller quantities and am able to complete them quickly. If you are searching for 9495 you may need to wait.

private void button1_Click(object sender, EventArgs e)
{
    string folderPath = @"C:\Users\Administrator\Desktop\test";//path_to_your_folder
    string[] filePrefixes = { "10x23", "45x23" }; // Add other prefixes
    int numBills = 25;//9495

    foreach (var filePrefix in filePrefixes)
    {
        var (missingFiles, duplicateFiles) = FindMissingOrDuplicateFiles(folderPath, filePrefix, numBills);

        Console.WriteLine($"Missing files for prefix {filePrefix}:");
        foreach (var missingFile in missingFiles)
        {
            Console.WriteLine(missingFile);
        }

        Console.WriteLine($"\nDuplicate files for prefix {filePrefix}:");
        foreach (var duplicateFile in duplicateFiles)
        {
            Console.WriteLine(duplicateFile);
        }
    }

}
static (List<string>, List<string>) FindMissingOrDuplicateFiles(string folderPath, string filePrefix, int numBills)
{
    var filesFound = new HashSet<string>();
    var missingFiles = new List<string>();
    var duplicateFiles = new List<string>();

    for (int i = 1; i <= numBills; i++)
    {
        string expectedFilename = $"{i}x{filePrefix}";
        string standardFilename = $"{expectedFilename}.pdf";

        if (File.Exists(Path.Combine(folderPath, standardFilename)))
        {
            filesFound.Add(standardFilename);
        }
        else
        {
            missingFiles.Add(standardFilename);
        }

        foreach (var file in Directory.GetFiles(folderPath))
        {
            var filename = Path.GetFileNameWithoutExtension(file);
            if (Regex.IsMatch(filename, $@"^{expectedFilename}\(\d+\)$"))
            {
                duplicateFiles.Add(filename + ".pdf");
            }
        }
    }

    return (missingFiles, duplicateFiles);
}

Best Regards,

Jiale

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