Develop Reference

Get Original file name in file sharing Xamarin.forms

I'm trying to implement the file sharing from other apps in Xamarin.Forms.
And I have some issues with Android implementation.
I'm referring to code of https://codemilltech.com/sending-files-to-a-xamarin-forms-app-part-2-android/.
if (Intent.Action == Intent.ActionSend)
{
var uriFromExtras = Intent.GetParcelableExtra(Intent.ExtraStream) as Android.Net.Uri;
string path = Intent.GetParcelableExtra(Intent.ExtraStream).ToString();
var subject = Intent.GetStringExtra(Intent.ExtraSubject);
// Get the info from ClipData
var pdf = Intent.ClipData.GetItemAt(0);
// Open a stream from the URI
var pdfStream = ContentResolver.OpenInputStream(pdf.Uri);
// Save it over
var memOfPdf = new System.IO.MemoryStream();
pdfStream.CopyTo(memOfPdf);
var docsPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);
var filePath = System.IO.Path.Combine(docsPath, "temp");
System.IO.File.WriteAllBytes(filePath, memOfPdf.ToArray());
mainForms.ShareFile(memOfPdf.ToArray(), System.IO.Path.GetFileName(path));
}
And I need to get the original name of shared file from File Manager.
Can anyone help me?

Here is a solution that gets the original file name of a shared file through an intent.
if (Intent.Action == Intent.ActionSend)
{
ClipData clip = Intent.ClipData;
Uri uri = clip.GetItemAt(0).Uri;
ICursor returnCursor = ContentResolver.Query(uri, null, null, null, null);
int nameIndex = returnCursor.GetColumnIndex(IOpenableColumns.DisplayName);
returnCursor.MoveToFirst();
var fileName = returnCursor.GetString(nameIndex);
Toast.MakeText(this,"fileName == " + fileName, ToastLength.Short).Show();
}
Examples: .png file and an xls file.

OutOfMemoryException error in Loop

I am trying to create a Windows app which uploads files to FTP. Essentially, it looks for .jpeg files in a given folder, it reads through the barcodes found in the .jpg files before uploading it into the FTP server, and entering the URL into the database for our records.
As there will be multiple files at any given time in the folder, I am essentially trying to read them in a loop, and process them accordingly. However, I get an OutOfMemoryException whenever the loop starts again. I am trying to figure out what I'm doing wrong here. I have appended my code below:
private void btnProcess_Click(object sender, RoutedEventArgs e)
{
podPath = Directory.GetFiles(DestPath, "*.jpg");
List<string> scans = new List<string>(podPath.Length);
List<string> badscans = new List<string>();
byte[] imageBytes;
string filename, result;
POD conpod = new POD();
OTPOD otpod = new OTPOD();
ConsignmentObj scanJob;
//Pickup OTScan;
//Consolidate ccv;
for (int i = 0; i < podPath.Count(); i++ )
{
filename = podPath[i].ToString();
using (Bitmap bm = (Bitmap)Bitmap.FromFile(filename))
{
var results = barcodeReader.Decode(bm);
result = results.ToString();
bm.Dispose();
}
if (result != null)
{
//if barcode can be read, we throw the value into the database to pull out relevant information
if (result.Contains(ConNotePrefix))
{
#region Consignments
scanJob = getCon(result.ToString());
final = ImageFolder + "\\" + result.ToString() + ".jpg";
using (System.Drawing.Image img = System.Drawing.Image.FromFile(filename))
{
MemoryStream ms = new MemoryStream();
try
{
img.Save(ms, ImageFormat.Jpeg);
imageBytes = ms.ToArray();
img.Dispose();
}
finally
{
ms.Flush();
ms.Close();
ms.Dispose();
}
}
lock (filename)
{
if (System.IO.File.Exists(filename))
{
File.Delete(filename);
}
}
using (var stream = File.Create(final)) { }
File.WriteAllBytes(final, imageBytes);
File.Delete(filename);
conpod.ConsignmentID = scanJob.ConsignmentID;
conpod.UserID = 1;
conpod.Location = ftpUrl + "//" + result.ToString() + ".jpg";
conpod.rowguid = Guid.NewGuid();
UploadFilesToFtp(ftpUrl, ftpUser, ftpPass, final, result.ToString() + ".jpg");
insertPOD(conpod);
scans.Add(result.ToString());
#endregion
}
}
else
{
badscans.Add(filename);
}
}
this.lbScans.ItemsSource = scans;
this.lbBadScans.ItemsSource = badscans;
}
The FTP method, UploadFilesToFtp(x, x, x, x, x, x) is not a problem here. All feedback will be much appreciated.

An OutOfMemoryException can also be thrown by the method FromFile of the Image class when
The file does not have a valid image format.
or
GDI+ does not support the pixel format of the file.
So i think there is a problem with one of your image files you are reading. One solution is to catch the OutOfMemoryException and adding the file to the badscans.
try{
using (Bitmap bm = (Bitmap)Bitmap.FromFile(filename)) {
var results = barcodeReader.Decode(bm);
result = results.ToString();
bm.Dispose();
}
}
catch(OutOfMemoryException) {
badscans.add(filename);
}

Image uploading in images folder issue in Asp.net

I am trying to upload JPG file to a folder I have created in my project.
The image does not get saved in the images folder. It displays my image when I upload but the image itself is not present in images folder.
Here is the code i am using:
private void btnUpload_Click(object sender, System.EventArgs e)
{
// Initialize variables
string sSavePath;
string sThumbExtension;
int intThumbWidth;
int intThumbHeight;
// Set constant values
sSavePath = "images/";
sThumbExtension = "_thumb";
intThumbWidth = 160;
intThumbHeight = 120;
// If file field isn’t empty
if (filUpload.PostedFile != null)
{
// Check file size (mustn’t be 0)
HttpPostedFile myFile = filUpload.PostedFile;
int nFileLen = myFile.ContentLength;
if (nFileLen == 0)
{
lblOutput.Text = "No file was uploaded.";
return;
}
// Check file extension (must be JPG)
if (System.IO.Path.GetExtension(myFile.FileName).ToLower() != ".jpg")
{
lblOutput.Text = "The file must have an extension of JPG";
return;
}
// Read file into a data stream
byte[] myData = new Byte[nFileLen];
myFile.InputStream.Read(myData,0,nFileLen);
// Make sure a duplicate file doesn’t exist. If it does, keep on appending an
// incremental numeric until it is unique
string sFilename = System.IO.Path.GetFileName(myFile.FileName);
int file_append = 0;
while (System.IO.File.Exists(Server.MapPath(sSavePath + sFilename)))
{
file_append++;
sFilename = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ file_append.ToString() + ".jpg";
}
// Save the stream to disk
System.IO.FileStream newFile
= new System.IO.FileStream(Server.MapPath(sSavePath + sFilename),
System.IO.FileMode.Create);
newFile.Write(myData,0, myData.Length);
newFile.Close();
// Check whether the file is really a JPEG by opening it
System.Drawing.Image.GetThumbnailImageAbort myCallBack =
new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
Bitmap myBitmap;
try
{
myBitmap = new Bitmap(Server.MapPath(sSavePath + sFilename));
// If jpg file is a jpeg, create a thumbnail filename that is unique.
file_append = 0;
string sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ sThumbExtension + ".jpg";
while (System.IO.File.Exists(Server.MapPath(sSavePath + sThumbFile)))
{
file_append++;
sThumbFile = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName) +
file_append.ToString() + sThumbExtension + ".jpg";
}
// Save thumbnail and output it onto the webpage
System.Drawing.Image myThumbnail
= myBitmap.GetThumbnailImage(intThumbWidth,
intThumbHeight, myCallBack, IntPtr.Zero);
myThumbnail.Save (Server.MapPath(sSavePath + sThumbFile));
imgPicture.ImageUrl = sSavePath + sThumbFile;
// Displaying success information
lblOutput.Text = "File uploaded successfully!";
// Destroy objects
myThumbnail.Dispose();
myBitmap.Dispose();
}
catch (ArgumentException errArgument)
{
// The file wasn't a valid jpg file
lblOutput.Text = "The file wasn't a valid jpg file.";
System.IO.File.Delete(Server.MapPath(sSavePath + sFilename));
}
}
}
public bool ThumbnailCallback()
{
return false;
}

I'd be surprised if the line myThumbnail.Save (Server.MapPath(sSavePath + sThumbFile)); works...
You are trying to map a file which doesn't exist yet!
Try
myThumbnail.Save(Server.MapPath(sSavePath) + sThumbFile));

Read Image file metadata

I want to upload an image file and then extract its basic information (author, dimensions, date created, modified, etc) and display it to the user. How can I do it.
A solution or reference to this problem in asp.net c# code would be helpful. But javascript or php would be ok as well.

Check this Link. You will get more Clearance about GetDetailsOf() and its File Properties based on the Win-OS version wise.
If you want to use C# code use below code to get Metadata's:
List<string> arrHeaders = new List<string>();
Shell shell = new ShellClass();
Folder rFolder = shell.NameSpace(_rootPath);
FolderItem rFiles = rFolder.ParseName(filename);
for (int i = 0; i < short.MaxValue; i++)
{
string value = rFolder.GetDetailsOf(rFiles, i).Trim();
arrHeaders.Add(value);
}

C# solution could be found here:
Link1
Link2

Bitmap image = new Bitmap(fileName);
PropertyItem[] propItems = image.PropertyItems;
foreach (PropertyItem item in propItems)
{
Console.WriteLine("iD: 0x" + item.Id.ToString("x"));
}
MSDN Reference
C# Tutorial Reference

try this...
private string doUpload()
{
// Initialize variables
string sSavePath;
sSavePath = "images/";
// Check file size (mustn’t be 0)
HttpPostedFile myFile = FileUpload1.PostedFile;
int nFileLen = myFile.ContentLength;
if (nFileLen == 0)
{
//**************
//lblOutput.Text = "No file was uploaded.";
return null;
}
// Check file extension (must be JPG)
if (System.IO.Path.GetExtension(myFile.FileName).ToLower() != ".jpg")
{
//**************
//lblOutput.Text = "The file must have an extension of JPG";
return null;
}
// Read file into a data stream
byte[] myData = new Byte[nFileLen];
myFile.InputStream.Read(myData, 0, nFileLen);
// Make sure a duplicate file doesn’t exist. If it does, keep on appending an
// incremental numeric until it is unique
string sFilename = System.IO.Path.GetFileName(myFile.FileName);
int file_append = 0;
while (System.IO.File.Exists(Server.MapPath(sSavePath + sFilename)))
{
file_append++;
sFilename = System.IO.Path.GetFileNameWithoutExtension(myFile.FileName)
+ file_append.ToString() + ".jpg";
}
// Save the stream to disk
System.IO.FileStream newFile
= new System.IO.FileStream(Server.MapPath(sSavePath + sFilename),
System.IO.FileMode.Create);
newFile.Write(myData, 0, myData.Length);
newFile.Close();
return sFilename;
}

Insert signature data into SQL Server in MVC 2 C#

I have working code that uses signature pad data to create and save a signature bmp image to a file location. My question is: how can I modify this code to insert the image into a SQL Server 2008 image field?
The following from my Controller obtains signature data from a signature tablet and creates a bmp image and saves it to a file location.
[PrincipalPermission(SecurityAction.Demand, Authenticated = true)]
public ActionResult SaveSignature2(IPrincipal principal) {
int userId = ((ScoutIdentity)principal.Identity).UserId.Value;
//Put user code to initialize the page here
SIGPLUSLib.SigPlus sigObj = new SIGPLUSLib.SigPlus();
sigObj.InitSigPlus();
sigObj.AutoKeyStart();
string visitorname = Request.Form["visitorname"];
visitorname = visitorname.Replace(" ", ""); //combines the first name with last name with no spaces
visitorname = visitorname.Trim();
string thevrvIDstr = Request.Form["vrvID"];
int thevrvID = Convert.ToInt32(thevrvIDstr);
//use the same data to decrypt signature
sigObj.AutoKeyData = Request.Form["SigText"];
sigObj.AutoKeyFinish();
sigObj.SigCompressionMode = 1;
sigObj.EncryptionMode = 2;
//Now, get sigstring from client
//Sigstring can be stored in a database if
//a biometric signature is desired rather than an image
sigObj.SigString = Request.Form["hidden"];
if (sigObj.NumberOfTabletPoints() > 0) {
sigObj.ImageFileFormat = 0;
sigObj.ImageXSize = 500;
sigObj.ImageYSize = 150;
sigObj.ImagePenWidth = 8;
sigObj.SetAntiAliasParameters(1, 600, 700);
sigObj.JustifyX = 5;
sigObj.JustifyY = 5;
sigObj.JustifyMode = 5;
long size;
byte[] byteValue;
sigObj.BitMapBufferWrite();
size = sigObj.BitMapBufferSize();
byteValue = new byte[size];
byteValue = (byte[])sigObj.GetBitmapBufferBytes();
sigObj.BitMapBufferClose();
System.IO.MemoryStream ms = new System.IO.MemoryStream(byteValue);
System.Drawing.Image img = System.Drawing.Image.FromStream(ms);
String path;
path = System.AppDomain.CurrentDomain.BaseDirectory;
path = path + "/uploadFiles/Signatures/"+thevrvIDstr+".bmp";
img.Save(path, System.Drawing.Imaging.ImageFormat.Bmp);
ViewData["Result"] = ("Image saved successfully to " + path);
}
else {
ViewData["Result"] = "signature has not been returned successfully!";
}
ViewData["Result"] = sigObj.SigString;
//return RedirectToAction("vrSignIn");
return View();
}
I also have code elsewhere in my controller that gets an uploaded file and inserts it into the database. This code works OK.
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult UploadTempFiles(string id, string u)
{
//this method temporarily stores files
string userIdString = Cryptographer.DecryptSymmetric("RijndaelManaged", SecurityImpl.UrlToBase64(u));
int userId = Convert.ToInt32(userIdString);
if (Request.Files.Count > 0)
{
for (int i = 0; i < Request.Files.Count; i++)
{
HttpPostedFileBase file = Request.Files[i];
int contentlength = file.ContentLength;
byte[] b = new byte[contentlength];
Stream s;
s = file.InputStream;
s.Read(b, 0, contentlength);
VisitRequest.AddVisitorSignature(userId, b);
}
}
return View("UploadFiles");
}
I'm thinking that I can use some part of the second code to interrupt the image creation process in the first code and insert the image into the database INSTEAD of saving the image to a file location. I don't know how to do that.

I had same problem, and I solved it:
Comment these three lines:
//path = System.AppDomain.CurrentDomain.BaseDirectory;
//path = path + "/uploadFiles/Signatures/"+thevrvIDstr+".bmp";
//img.Save(path, System.Drawing.Imaging.ImageFormat.Bmp);
Convert image to String data (assumed that your variable 'strSignature' was declared before):
strSignature = img.ToString();
Save it with your Stored Procedure.
Hope this help you!