Develop Reference

c# how to save IO.Stream to MemoryStream and save to PDF file on local folder

I am calling a third party service, which return a pdf file by IO.Stream. I need to change to MemoryStream, and save to a pdf file.

cRequestString = ".....";//You need to set up you own URL here.
//Make the API call
try
{
byte[] bHeaderBytes = System.Text.Encoding.UTF8.GetBytes(GetUserPasswordString()); //user and pa for third party call.
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(cRequestString);
request.Method = WebRequestMethods.Http.Get;
request.PreAuthenticate = true;
request.ContentType = "application/pdf";
request.Accept = "application/pdf";
request.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(bHeaderBytes));
MemoryStream memStream;
WebResponse response = request.GetResponse();
using (Stream stream = response.GetResponseStream())
using (StreamReader reader = new StreamReader(stream))
{
memStream = new MemoryStream();
//read small blocks to show correctly
byte[] buffer = new Byte[1023];
int byteCount;
do
{
byteCount = stream.Read(buffer, 0, buffer.Length);
memStream.Write(buffer, 0, byteCount);
} while (byteCount > 0);
}
memStream.Seek(0, SeekOrigin.Begin);//set position to beginning
return memStream;
}
catch
{
return null;
}
//save MemoryStream to local pdf file
private void SavePDFFile(string cReportName, MemoryStream pdfStream)
{
//Check file exists, delete
if (File.Exists(cReportName))
{
File.Delete(cReportName);
}
using (FileStream file = new FileStream(cReportName, FileMode.Create, FileAccess.Write))
{
byte[] bytes = new byte[pdfStream.Length];
pdfStream.Read(bytes, 0, (int)pdfStream.Length);
file.Write(bytes, 0, bytes.Length);
pdfStream.Close();
}
}

You could do the following.
using (Stream stream = response.GetResponseStream())
using(MemoryStream memStream = new MemoryStream())
{
memStream = new MemoryStream();
stream.CopyTo(memoryStream);
// TODO : Rest of your task
}
More details on Stream.CopyTo on MSDN

Exporting byte[] results to corrupted .zip

I am trying to make a CLR with .NET 2.0 integrated into MS SQL Server 2008. I call an API with and I should receive a .zip as response. I store the response into a Stream and I want to export this file to a physical .zip file.
I tried exporting the file with C# and SQL (BCB OR OLE) and all resulted into a corrupted file. So, I believe I am doing something wrong with in the making of the stream.
The C# code is the following:
private static byte[] GetStreamFileResult(Cookie loginCookie, Guid fileGuid, String baseUri)
{
byte[] output = null;
//String result = null;
string url = "some url"
CookieContainer cookies = new CookieContainer();
cookies.Add(new Uri(url), loginCookie);
WebRequest request = WebRequest.Create(url);
(request as HttpWebRequest).CookieContainer = cookies;
WebResponse response = request.GetResponse();
HttpWebResponse resp = response as HttpWebResponse;
Stream dataStream = response.GetResponseStream();
using (MemoryStream ms = new MemoryStream())
{
CopyStream(dataStream, ms);
output = ms.ToArray();
}
dataStream.Close();
response.Close();
return output;
}
The C# code to export the zip is the following:
File.WriteAllBytes("C:\\folder\\t.zip", stream); // Requires System.IO
The copy from stream to stream:
public static void CopyStream(Stream input, Stream output)
{
if (input != null)
{
using (StreamReader reader = new StreamReader(input))
using (StreamWriter writer = new StreamWriter(output))
{
writer.Write(reader.ReadToEnd());
}
}
}

Your CopyStream is broken. You need to talk binary. You're currently treating binary zip data as though it were text:
byte[] buffer = new byte[2048];
int bytesRead;
while((bytesRead = input.Read(buffer, 0, buffer.Length)) > 0) {
output.Write(buffer, 0, bytesRead);
}

Binary stream '0' does not contain a valid BinaryHeader. invalid stream or object version change

I know like this question is existed but they not help to me, I want post a file of an action to ConvertToFLV action then that return an object converted to byte[], now when I want convert it to object I get The following error in ByteArrayToObject method, when reach to this line Video obj = (Video)binForm.Deserialize(memStream)
Binary stream '0' does not contain a valid BinaryHeader. Possible causes are invalid stream or object version change between serialization and deserialization.
In addition please tell me contentType is correct in ConvertToFLV action?
public ActionResult Index()
{
WebRequest request = WebRequest.Create("http://localhost:25220/home/ConvertToFLV");
request.Method = "POST";
string path = Request.MapPath("~") + "2.wmv";
byte[] byteArray = System.IO.File.ReadAllBytes(path);
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = byteArray.Length;
Stream dataStream = request.GetRequestStream();
dataStream.Write(byteArray, 0, byteArray.Length);
dataStream.Close();
WebResponse response = request.GetResponse();
dataStream = response.GetResponseStream();
byte[] convertedBytes = new byte[(int)response.ContentLength];
dataStream.Read(convertedBytes, 0, (int)response.ContentLength);
var obj = ByteArrayToObject(convertedBytes);
dataStream.Close();
response.Close();
return View();
}
public FileResult ConvertToFLV(HttpPostedFileBase file)
{
Stream stream = HttpContext.Request.InputStream;
byte[] result = new byte[HttpContext.Request.ContentLength];
stream.Read(result, 0, HttpContext.Request.ContentLength);
Video video = new Video { FLV = result };
return File(ObjectToByteArray(video), "application/x-www-form-urlencoded");
}
private Object ByteArrayToObject(byte[] arrBytes)
{
MemoryStream memStream = new MemoryStream();
memStream.Position = 0;
BinaryFormatter binForm = new BinaryFormatter();
memStream.Write(arrBytes, 0, arrBytes.Length);
memStream.Seek(0, SeekOrigin.Begin);
Video obj = (Video)binForm.Deserialize(memStream);
return obj;
}
private byte[] ObjectToByteArray(Video obj)
{
if (obj == null)
return null;
BinaryFormatter bf = new BinaryFormatter();
MemoryStream ms = new MemoryStream();
bf.Serialize(ms, obj);
return ms.ToArray();
}

Forward posted image to WCF Rest Service

I have a webform application written in C# and what I want to do is after the user submits a HTML form with an image, I send that image to a WCF Rest service also written in C#.
The problem is when I get the image in the web service this is corrupted.
I guess that the problem is that I don't encode the file properly, but after days of reading on internet I haven't found a clue.
Webform code:
protected void Page_Load(object sender, EventArgs e)
{
HttpPostedFile image = Request.Files["imagen"];
string serverResponse = Send("mywebservice/postimage", "POST", Encoding.UTF8.GetBytes(StreamToString(image.InputStream)));
}
Edit (this way worked)
protected void Page_Load(object sender, EventArgs e)
{
HttpPostedFile image = Request.Files["imagen"];
MemoryStream ms = new MemoryStream();
image.InputStream.CopyTo(ms);
byte[] bytes = ms.ToArray();
string serverResponse = Send("mywebservice/postimage", "POST", bytes);
}
public int Send(string url, string method, byte[] data)
{
string serverResponse = "";
HttpWebRequest newRequest = (HttpWebRequest)WebRequest.Create(url);
newRequest.ContentType = "image/jpeg";
newRequest.Method = method;
newRequest.Timeout = 10000;
if (newRequest.Method == "POST" || newRequest.Method == "PUT")
{
Stream reqStream = newRequest.GetRequestStream();
reqStream.Write(data, 0, data.Length);
reqStream.Close();
}
WSMessageEnt wsMessageEnt = new WSMessageEnt();
try
{
HttpWebResponse webResponse;
webResponse = (HttpWebResponse)newRequest.GetResponse();
Stream dataStream = webResponse.GetResponseStream();
serverResponse = new StreamReader(dataStream).ReadToEnd();
}
catch (WebException we)
{
}
return serverResponse;
}
public static string StreamToString(Stream data)
{
StreamReader reader = new StreamReader(data);
string body = reader.ReadToEnd();
reader.Close();
reader.Dispose();
return body;
}
Webservice code:
[WebInvoke(UriTemplate = "upload-user-image", Method = "POST")]
public Stream UploadUserImage(Stream streamdata)
{
System.Drawing.Image img = System.Drawing.Image.FromStream(streamImagen, true);
// here I get a format error
}

Possibly one problem: you're converting a stream of bytes, into a string, then back to a stream of bytes. The image bytes are arbitrary bytes, which may or may not map to a string, and the encoding you're using in one conversion (Encoding.Default) may not be the same as the one used in the other (Encoding.UTF8).
Instead of doing this:
Encoding.UTF8.GetBytes(StreamToString(image.InputStream))
Try doing something like
MemoryStream ms = new MemoryStream();
image.InputStream.CopyTo(ms);
byte[] bytes = ms.ToArray();
Or just pass the stream to Send and copy it to the request stream.

Convert a base64string back to byte[]

I want to use C# to convert a byteArray to base64string by using Convert.ToBase64String(), then I want to send this string to save using MySQL by sending post data to a PHP page. My problem is I can't convert this string back to a byteArray using this method as after this string is retrieved from the PHP page (after it got data from MySQL), it tells me that argument on method Convert.FromBase64String() was wrong.
I don't where is problem occurs, how can I solve it?
My code:
public static string BitmapToString(BitmapImage img)
{
try
{
WriteableBitmap bmp = new WriteableBitmap(img);
byte[] byteArray = null;
string str = null;
MemoryStream stream = new MemoryStream();
bmp.SaveJpeg(stream, bmp.PixelWidth, bmp.PixelHeight, 0, 100);
byteArray = stream.ToArray();
str = Convert.ToBase64String(byteArray);
return str;
}
catch (System.Exception ex)
{
Console.WriteLine(ex.StackTrace);
}
return null;
}
public static BitmapImage StringToBitmap(string str)
{
try
{
byte[] byteArray = Convert.FromBase64String(str);
Stream memStream = new MemoryStream(byteArray);
BitmapImage img = null;
MemoryStream stream = new MemoryStream(byteArray);
stream.Seek(0, SeekOrigin.Begin);
img = new BitmapImage();
img.SetSource(stream);
return img;
}
catch (System.Exception ex)
{
Console.WriteLine(ex.StackTrace);
}
return null;
}

Convert.FromBase64String() will work for Convert.ToBase64String() results but there can be inputs in your aplication which not converted to Base64String, those cases might fail.
This is not be a issue with those two methods. Check Convert.ToBase64String() result and what you get when you read it from database.