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Сreating a file in memory

There is a question.
I need to put a separate ini file into the archive.
BUT I don't want to collect and store this file on disk.
Is it possible to collect a file and place it in an archive without saving it to disk?
Now the archive is going like this.
var memoryStream = new MemoryStream();
var response = new HttpResponseMessage(HttpStatusCode.OK);
var filepaths = Directory.GetFiles(setting.DirMicroSip);
using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
{
foreach(string filepath in filepaths)
{
string filename = Path.GetFileName(filepath);
var entry = archive.CreateEntry(filename);
using (var file = File.OpenRead(Path.Combine(setting.DirMicroSip, filename)))
using (var entryStream = entry.Open())
{
await file.CopyToAsync(entryStream);
}
}
}
memoryStream.Position = 0;
response.Content = new StreamContent(memoryStream);
response.Content.Headers.ContentLength = memoryStream.Length;
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = "Archive.zip"
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/zip");
return response;
And ini on the disk like this.
var ini = new IniFile("C:/arh/MicroSIP_test.ini");
ini.Write("accountId", "1", "Settings");
ini.Write("singleMode", "1", "Settings");...
Help me please

Encrypting file conent and decrypt it while reading C#

I am using entity framework(WebAPI/C#/VS2019) and using below code to save file and display file.
Save Code
Document document = new Document();
var plainTextBytes = System.Text.Encoding.UTF8.GetBytes(attachment_data); //attachment_data is string
document.document_content=plainTextBytes;//document_content is byte[]
db.Documents.Add(document);
db.SaveChanges();
Below code is used to show saved file
[Route("api/documents/download")]
[HttpGet]
public HttpResponseMessage Download(int documentid)
{
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
var document = db.Documents.Where(e => e.id.Equals(documentid)).FirstOrDefault();
if (document != null)
{
var stream = new System.IO.MemoryStream(document.document_content);
result.Content = new StreamContent(stream);
result.Content.Headers.ContentType =
new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = document.name
};
}
return result;
}
Both Save file and downloading file is working fine.
The issue is how to encrypt the file content before Saving to Database?I saw few SO links but most of the methods are taking string as input and string as output.Not sure which one will fit in this scenario.

Returning a zipfile from a web api

I have built an asp net web api. I need to return a zipfile, as a result of some inner logic. I'm using this code and it works, but the resulting zip file, when unzipped manually, gave me this error "There are data after the end of the payload"
using (ZipFile zip = new ZipFile())
{
...
zip.Save(di.FullName + "\\" + "Update.zip");
}
string path = Path.Combine(Properties.Settings.Default.PathDisposizioniHTML, "Update.zip");
var response = new HttpResponseMessage(HttpStatusCode.OK);
var stream = new System.IO.FileStream(path, System.IO.FileMode.Open);
response.Content = new StreamContent(stream);
response.Content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("application/octet-stream");
This is how i receive the data in a .net console application:
using (Stream output = File.OpenWrite(#"C:\prova\MyFile.zip"))
using (Stream input = httpResponse.GetResponseStream())
{
input.CopyTo(output);
}

If you already have the zip file on your system, you shouldn't need to do anything special before sending it as a response.
This should work:
string filePath = #"C:\myfolder\myfile.zip";
return File(filePath, "application/zip");
If you're making the file on the fly, i.e. getting other files and programatically putting them into a zip file for the user, the following should work:
public IActionResult GetZipFile(){
//location of the file you want to compress
string filePath = #"C:\myfolder\myfile.ext";
//name of the zip file you will be creating
string zipFileName = "zipFile.zip";
byte[] result;
using (MemoryStream zipArchiveMemoryStream = new MemoryStream())
{
using (ZipArchive zipArchive = new ZipArchive(zipArchiveMemoryStream, ZipArchiveMode.Create, true))
{
ZipArchiveEntry zipEntry = zipArchive.CreateEntry(zipFileName);
using (Stream entryStream = zipEntry.Open())
{
using (MemoryStream tmpMemory = new MemoryStream(System.IO.File.ReadAllBytes(filePath)))
{
tmpMemory.CopyTo(entryStream);
};
}
}
zipArchiveMemoryStream.Seek(0, SeekOrigin.Begin);
result = zipArchiveMemoryStream.ToArray();
}
return File(result, "application/zip", zipFileName);
}
This is taken from a recent ASP.NET project of my own.

Convert LINQ result to CSV or Excel

Using a LINQ query I need to export to Excel when a WebApi method is called. I have built the LINQ query that will return the correct data, now I need it to export to .csv or Excel file format.
I have tried using MemoryStream and StreamWriter but I think I am just chasing my tail now.
[HttpGet]
[Route("Download")]
public Task<IActionResult> Download(int memberId)
{
var results = (from violations in _db.tblMappViolations
where violations.MemberID == memberId
select new IncomingViolations
{
Contact = violations.ContactName,
Address = violations.str_Address,
City = violations.str_City,
State = violations.str_State,
Zip = violations.str_Zipcode,
Country = violations.str_Country,
Phone = violations.str_Phone,
Email = violations.str_Email,
Website = violations.str_WebSite,
}).FirstOrDefault();
MemoryStream stream = new MemoryStream(results);
StreamWriter writer = new StreamWriter(stream);
writer.Flush();
stream.Position = 0;
FileStreamResult response = File(stream, "application/octet-stream");
response.FileDownloadName = "violations.csv";
return response;
}

Here is how you can send CSV file to the user from server.
string attachment = "attachment; filename=MyCsvLol.csv";
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.ClearHeaders();
HttpContext.Current.Response.ClearContent();
HttpContext.Current.Response.AddHeader("content-disposition", attachment);
HttpContext.Current.Response.ContentType = "text/csv";
HttpContext.Current.Response.AddHeader("Pragma", "public");
var sb = new StringBuilder();
// Add your data into stringbuilder
sb.Append(results.Contact);
sb.Append(results.Address);
sb.Append(results.City);
// and so on
HttpContext.Current.Response.Write(sb.ToString());
For Sending it from API
MemoryStream stream = new MemoryStream();
StreamWriter writer = new StreamWriter(stream);
// Write Your data here in writer
writer.Write("Hello, World!");
writer.Flush();
stream.Position = 0;
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
result.Content = new StreamContent(stream);
result.Content.Headers.ContentType = new MediaTypeHeaderValue("text/csv");
result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") { FileName = "Export.csv" };
return result;
Update:-
public HttpResponseMessage Download()
{
var results = (from violations in _db.tblMappViolations
where violations.MemberID == memberId
select new IncomingViolations
{
Contact = violations.ContactName,
Address = violations.str_Address,
City = violations.str_City,
State = violations.str_State,
Zip = violations.str_Zipcode,
Country = violations.str_Country,
Phone = violations.str_Phone,
Email = violations.str_Email,
Website = violations.str_WebSite,
});
var sb = new StringBuilder();
MemoryStream stream = new MemoryStream();
StreamWriter writer = new StreamWriter(stream);
foreach(var tempResult in results)
{
sb.Append(tempResult.Contact+",");
sb.Append(tempResult.Address+",");
sb.Append(tempResult.City+",");
sb.Append(tempResult.State+",");
sb.Append(tempResult.Zip+",");
sb.Append(tempResult.Country+",");
sb.Append(tempResult.Phone+",");
sb.Append(tempResult.Email+",");
sb.Append(tempResult.Website+",");
sb.Append(Enviroment.NewLine);
}
writer.Write(sb.ToString());
writer.Flush();
stream.Position = 0;
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
result.Content = new StreamContent(stream);
result.Content.Headers.ContentType = new MediaTypeHeaderValue("text/csv");
result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") { FileName = "Export.csv" };
return result;
}

First, to reuse the code in other areas, always create helper classes.
I adopted this method of converting list into a stream with headers as property names, if you want a file from this, essentially, I would just add another step to this:
STEP 1:
public static Stream ConvertToCSVStream<T>(IEnumerable<T> objects)
{
Type itemType = typeof(T);
var properties = itemType.GetProperties();
var mStream = new MemoryStream();
StreamWriter sWriter = new StreamWriter(mStream);
var values = objects.Select(o =>
{
return string.Join(",", properties.Select(p =>
{
var value = p.GetValue(o).ToString();
if (!Regex.IsMatch(value, "[,\"\\r\\n]"))
{
return value;
}
value = value.Replace("\"", "\"\"");
return string.Format("\"{0}\"", value);
})) + sWriter.NewLine;
});
var valuesInStrings = values.Aggregate((current, next) => current + next);
try
{
sWriter.Write(string.Join(",", properties.Select(x => x.Name.Replace("_", " "))) + sWriter.NewLine);
sWriter.Write(valuesInStrings);
}
catch (Exception e)
{
mStream.Close();
throw e;
}
sWriter.Flush();
mStream.Position = 0;
return mStream;
}
if your data is text, just convert it directly to a file result but if not, you must convert it to binary array and write it to stream, refer to this article for converting it to binary data, in our case, for csv, you could just use the FileStream result that you've implemented in a separate method:
STEP 2:
public FileStreamResult CreateFile(MemoryStream mStream, string path, string name)
{
//set values, names, content type, etc
//return filestream
}
or any other method you find better.

Save your result in a DataTable and then just use this
XLWorkbook workbook = new XLWorkbook();
DataTable table = GetYourTable();
workbook.Worksheets.Add(table);
And you should definitely use stream writer for this if you know which file its going to write to from the start, else stream reader and then stream writer.

How can I convert IEnumerable<CustomType> to Byte64 for file download

I'm using WebApiContrib.Formatting.xlsx to create and download a Microsoft Excel file. My problem is that when called from the client the file can't be opened and several method were tried. When dealing with PDF the problem was resolved converting the output to Byte64 like this:
var response = new HttpResponseMessage
{
Content = new StringContent(Convert.ToBase64String(output.ToArray()))
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = "Report.pdf"
};
return response;
In the case of WebApiContrib.Formatting.xlsx I have an IEnumerable. How can convert it the same way as the PDF.
var subscriptionExcelModels = subscriptionPlansConverted as SubscriptionExcelModel[] ?? subscriptionPlansConverted.ToArray();
This is my snippet of the last part of the code for the excel file:
var ret = Request.CreateResponse(HttpStatusCode.OK,subscriptionExcelModels);
ret.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
ret.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = "Report.xlsx"
};
return ret;