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Using BitmapImage created on Threadpool thread
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InvalidOperationException delegation UI Thread C#
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Closed 3 years ago.
I'm having a lot of pain porting my picturebox from Windows Form to WPF.
My problem is not about the picturebox itself, but I'm having troubles displaying an image gotten from NetworkStream from a Thread into an Image in WPF.
I got this NetworkStream from a TcpClient connection client-server.
This is my Windows Form code (relevant part):
Thread getImage;
void StartReceiving(){
getImage = new Thread(ReceiveImage);
getImage.Start();
}
private void ReceiveImage()
{
BinaryFormatter binaryFormatter = new BinaryFormatter();
while (client.Connected)
{
mainStream = client.GetStream();
try
{
pictureBox1.Image = (Image)binaryFormatter.Deserialize(mainStream);
}
catch (Exception ex) { }
}
}
This code works, I get image in loop every 100 ms and I need to update that source.
In WPF I tried with an Image and setting it's source (I tried both UriSource and StreamSource) but no success. I got thread exceptions, "nothing appens" errors, ...
This is my last code, it results into a Thread error but I don't know what else to try to make it thread compliant. (I only posted the relevant part)
private readonly Thread getImage;
public SecondWindow(int port)
{
InitializeComponent();
client = new TcpClient();
getImage = new Thread(new ThreadStart(ReceiveImage));
while (!client.Connected)
{
server.Start();
client = server.AcceptTcpClient();
}
getImage.Start();
}
private void ReceiveImage()
{
BinaryFormatter binaryFormatter = new BinaryFormatter();
BitmapImage imgSrc = new BitmapImage();
while (client.Connected)
{
var mainStream = client.GetStream();
int loop = 0;
while (!mainStream.DataAvailable && loop < 500)
{
loop++;
Thread.Sleep(10);
}
if (mainStream.DataAvailable)
{
try
{
imgSrc = new BitmapImage();
imgSrc.BeginInit();
imgSrc.StreamSource = mainStream;
imgSrc.CacheOption = BitmapCacheOption.OnLoad;
imgSrc.EndInit();
if (imgSrc.CanFreeze && !imgSrc.IsFrozen)
imgSrc.Freeze();
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
if (displayImage.Dispatcher.CheckAccess())
{
displayImage.Source = imgSrc;
}
else
{
Action act = () => { displayImage.Source = imgSrc; };
displayImage.Dispatcher.BeginInvoke(act);
}
}
}
}
In the above code I have 2 problems: 1st that imgSrc can never freeze
2nd (probably a direct consequence of 1st problem), I get InvalidOperationException The calling thread cannot access this object because a different thread owns it
Thanks all for the support
I solved!! the solution was using some other methods in order to deserialize the full stream and then apply it to the image source!
This might not be the best solution but this answer pointed me to the end of this agony
This is my working code:
[DllImport("gdi32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
internal static extern bool DeleteObject(IntPtr value);
private void ReceiveImage()
{
BinaryFormatter binaryFormatter = new BinaryFormatter();
System.Drawing.Image imgSrc;
while (client.Connected)
{
var mainStream = client.GetStream();
int loop = 0;
while (!mainStream.DataAvailable && loop < 500)
{
loop++;
Thread.Sleep(10);
}
if (mainStream.DataAvailable)
{
try
{
imgSrc = (System.Drawing.Image)binaryFormatter.Deserialize(mainStream);
var bitmap = new Bitmap(imgSrc);
IntPtr bmpPt = bitmap.GetHbitmap();
BitmapSource bitmapSource =
System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
bmpPt,
IntPtr.Zero,
Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
//freeze bitmapSource and clear memory to avoid memory leaks
if (bitmapSource.CanFreeze && !bitmapSource.IsFrozen)
bitmapSource.Freeze();
DeleteObject(bmpPt);
if (displayImage.Dispatcher.CheckAccess())
{
displayImage.Source = bitmapSource;
}
else
{
Action act = () => { displayImage.Source = bitmapSource; };
displayImage.Dispatcher.BeginInvoke(act);
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
}
}
Related
So, i have a function that will load an image from disk async in an other thread ( big images will be loaded and I don't want the UI THread to be locked while loading).
Loading is done like this
public override void LoadFile()
{
using (var imageStream = new FileStream(_filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
Decoder = new TiffBitmapDecoder(imageStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.OnLoad);
InitializeFile();
}
}
Then I want to use the Decoder on the main thread
public List<ThumbnailModel> LoadPages()
{
var result = new List<ThumbnailModel>();
foreach (var frame in Decoder.Frames) <--// this line throws exception
{
result.Add(new ThumbnailModel
{
Name = _metadataLoader.GetPageName((BitmapMetadata)frame.Metadata),
Bitmap = new WriteableBitmap(frame)
});
}
return result;
}
Now here is the problem, whenever I reach the line where I try to access the Decoder.Frames it throws exception (The calling thread cannot access this object because a different thread owns it.)
Is there a way I can use my Decoder in the main thread if not, the only possible solution is to load all the image information in the other thread?
Full code version :
// this is the task, that calls the imageFactory LoadFile method - NewThread
private async Task OpenFileAsync(string strFilePath)
{
var newFile = _imageFileFactory.LoadFile(strFilePath);
if (newFile != null)
{
_imagefile = newFile;
}
}
//image factory load file - NewThread
public IImageFile LoadFile(string filePath)
{
if (string.IsNullOrWhiteSpace(filePath))
{
return null;
}
var fileExtension = Path.GetExtension(filePath); // .tiff or .jpeg
var file = new ImageFileTiff(filePath, _metatadaFactory, _metadataVersioner);
file.LoadFile();
return file;
}
// ImageFileTiff LoadFile will create a decoder - NewThread
public override void LoadFile()
{
using (var imageStream = new FileStream(_filePath, FileMode.Open, FileAccess.Read, FileShare.Read))
{
Decoder = new JpegBitmapDecoder(imageStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.OnLoad);
InitializeFile();
}
}
After we have an IImageFile we call on MainThread(UIThread)
var pages = _imagefile.LoadPages();
Where LoadPages is the place where the app breaks. also called on UIThread
public List LoadPages()
{
var result = new List();
foreach (var frame in Decoder.Frames)
{
result.Add(new ThumbnailModel
{
Name = _metadataLoader.GetPageName((BitmapMetadata)frame.Metadata),
Bitmap = new WriteableBitmap(frame)
});
}
return result;
}
I thought you could simply return the decoder from the thread to be able to access it but your decoder is a TiffBitmapDecoder which inherits from DispatcherObject (https://learn.microsoft.com/en-gb/dotnet/api/system.windows.threading.dispatcherobject?view=netcore-3.1).
So you won't be able to access it from a different thread than the one where it was created msdn:"Only the thread that the Dispatcher was created on may access the DispatcherObject directly"
What you could do instead is use the decoder in it's thread and return the final result:
I couldn't build on your sample since there was to much missing for me to test it but I built a similar project to give an exemple:
public partial class MainWindow : Window
{
public MainWindow()
{
}
public TiffBitmapDecoder LoadFile()
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.InitialDirectory = "c:\\";
openFileDialog.Filter = "tiff files (*.tif)|*.tif|All files (*.*)|*.*";
openFileDialog.FilterIndex = 2;
openFileDialog.RestoreDirectory = true;
if (openFileDialog.ShowDialog() == true && !string.IsNullOrEmpty(openFileDialog.FileName))
{
//I didn't bother to check the file extension since it's just an exemple
using (var imageStream = openFileDialog.OpenFile())
{
return new TiffBitmapDecoder(imageStream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.OnLoad);
}
}
else
{
//User cancelled
return null;
}
}
public List<ThumbnailModel> LoadPages(TiffBitmapDecoder decoder)
{
//TiffBitmapDecoder" inherits from DispatcherObject/>
//https://learn.microsoft.com/en-gb/dotnet/api/system.windows.threading.dispatcherobject?view=netcore-3.1
var result = new List<ThumbnailModel>();
if (decoder != null)
{
try
{
foreach (var frame in decoder.Frames)
{
result.Add(new ThumbnailModel
{
//set the variables
});
}
}
catch(InvalidOperationException e)
{
MessageBox.Show(e.Message, "Error");
}
}
else
{
//Nothing to do
}
return result;
}
private async Task AsyncLoading()
{
this.thumbnailModels = await Task.Run<List<ThumbnailModel>>(() =>
{
var decoder = this.LoadFile();
return this.LoadPages(decoder);
});
}
private List<ThumbnailModel> thumbnailModels = null;
private async void AsyncLoadingButton_Click(object sender, RoutedEventArgs e)
{
await this.AsyncLoading();
}
}
public class ThumbnailModel
{
}
Content of MainWindow.xaml just in case:
<Grid>
<StackPanel Orientation="Vertical">
<Button x:Name="NoReturnButton" Margin="10" HorizontalAlignment="Center" Content="Call AsyncLoadingNoReturn" Click="AsyncLoadingButton_Click" />
</StackPanel>
</Grid>
Hello I'm writing a WPF program that gets has thumbnails inside a ThumbnailViewer. I want to generate the Thumbnails first, then asynchronously generate the images for each thumbnail.
I can't include everything but I think this is whats relevant
Method to generate the thumbnails.
public async void GenerateThumbnails()
{
// In short there is 120 thumbnails I will load.
string path = #"C:\....\...\...png";
int pageCount = 120;
SetThumbnails(path, pageCount);
await Task.Run(() => GetImages(path, pageCount);
}
SetThumbnails(string path, int pageCount)
{
for(int i = 1; i <= pageCount; i ++)
{
// Sets the pageNumber of the current thumbnail
var thumb = new Thumbnail(i.ToString());
// Add the current thumb to my thumbs which is
// binded to the ui
this._viewModel.thumbs.Add(thumb);
}
}
GetImages(string path, int pageCount)
{
for(int i = 1; i <= pageCount; i ++)
{
Dispatcher.Invoke(() =>
{
var uri = new Uri(path);
var bitmap = new BitmapImage(uri);
this._viewModel.Thumbs[i - 1].img.Source = bitmap;
});
}
}
When I run the code above it works just as if I never add async/await/task to the code. Am I missing something? Again What I want is for the ui to stay open and the thumbnail images get populated as the GetImage runs. So I should see them one at a time.
UPDATE:
Thanks to #Peregrine for pointing me in the right direction. I made my UI with custom user controls using the MVVM pattern. In his answer he used it and suggested that I use my viewModel. So what I did is I add a string property to my viewModel and made an async method that loop though all the thumbnails and set my string property to the BitmapImage and databound my UI to that property. So anytime it would asynchronously update the property the UI would also update.
The Task that runs GetImages does virtually nothing but Dispatcher.Invoke, i.e. more or less all your code runs in the UI thread.
Change it so that the BitmapImage is created outside the UI thread, then freeze it to make it cross-thread accessible:
private void GetImages(string path, int pageCount)
{
for (int i = 0; i < pageCount; i++)
{
var bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.CacheOption = BitmapCacheOption.OnLoad;
bitmap.UriSource = new Uri(path);
bitmap.EndInit();
bitmap.Freeze();
Dispatcher.Invoke(() => this._viewModel.Thumbs[i].img.Source = bitmap);
}
}
You should also avoid any async void method, excpet when it is an event handler. Change it as shown below, and await it when you call it:
public async Task GenerateThumbnails()
{
...
await Task.Run(() => GetImages(path, pageCount));
}
or just:
public Task GenerateThumbnails()
{
...
return Task.Run(() => GetImages(path, pageCount));
}
An alternative that altogether avoids async/await is a view model with an ImageSource property whose getter is called asynchronously by specifying IsAsync on the Binding:
<Image Source="{Binding Image, IsAsync=True}"/>
with a view model like this:
public class ThumbnailViewModel
{
public ThumbnailViewModel(string path)
{
Path = path;
}
public string Path { get; }
private BitmapImage îmage;
public BitmapImage Image
{
get
{
if (îmage == null)
{
îmage = new BitmapImage();
îmage.BeginInit();
îmage.CacheOption = BitmapCacheOption.OnLoad;
îmage.UriSource = new Uri(Path);
îmage.EndInit();
îmage.Freeze();
}
return îmage;
}
}
}
It looks as though you've been mislead by the constructor of BitmapImage that can take a Url.
If this operation really is slow enough to justify using the async-await pattern, then you would be much better off dividing it into two sections.
a) Fetching the data from the url. This is the slow part - it's IO bound, and would benefit most from async-await.
public static class MyIOAsync
{
public static async Task<byte[]> GetBytesFromUrlAsync(string url)
{
using (var httpClient = new HttpClient())
{
return await httpClient
.GetByteArrayAsync(url)
.ConfigureAwait(false);
}
}
}
b) Creating the bitmap object. This needs to happen on the main UI thread, and as it's relatively quick anyway, there's no gain in using async-await for this part.
Assuming that you're following the MVVM pattern, you shouldn't have any visual elements in the ViewModel layer - instead use a ImageItemVm for each thumbnail required
public class ImageItemVm : ViewModelBase
{
public ThumbnailItemVm(string url)
{
Url = url;
}
public string Url { get; }
private bool _fetchingBytes;
private byte[] _imageBytes;
public byte[] ImageBytes
{
get
{
if (_imageBytes != null || _fetchingBytes)
return _imageBytes;
// refresh ImageBytes once the data fetching task has completed OK
Action<Task<byte[]>> continuation = async task =>
{
_imageBytes = await task;
RaisePropertyChanged(nameof(ImageBytes));
};
// no need for await here as the continuations will handle everything
MyIOAsync.GetBytesFromUrlAsync(Url)
.ContinueWith(continuation,
TaskContinuationOptions.OnlyOnRanToCompletion)
.ContinueWith(_ => _fetchingBytes = false)
.ConfigureAwait(false);
return null;
}
}
}
You can then bind the source property of an Image control to the ImageBytes property of the corresponding ImageItemVm - WPF will automatically handle the conversion from byte array to a bitmap image.
Edit
I misread the original question, but the principle still applies. My code would probably still work if you made a url starting file:// but I doubt it would be the most efficient.
To use a local image file, replace the call to GetBytesFromUrlAsync() with this
public static async Task<byte[]> ReadBytesFromFileAsync(string fileName)
{
using (var file = new FileStream(fileName,
FileMode.Open,
FileAccess.Read,
FileShare.Read,
4096,
useAsync: true))
{
var bytes = new byte[file.Length];
await file.ReadAsync(bytes, 0, (int)file.Length)
.ConfigureAwait(false);
return bytes;
}
}
Rather than involving the the dispatcher and jumping back and forth, I'd do something like this:
private Task<BitmapImage[]> GetImagesAsync(string path, int pageCount)
{
return Task.Run(() =>
{
var images = new BitmapImage[pageCount];
for (int i = 0; i < pageCount; i++)
{
var bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.CacheOption = BitmapCacheOption.OnLoad;
bitmap.UriSource = new Uri(path);
bitmap.EndInit();
bitmap.Freeze();
images[i] = bitmap;
}
return images;
}
}
Then, on the UI thread calling code:
var images = await GetImagesAsync(path, pageCount);
for (int i = 0; i < pageCount; i++)
{
this._viewModel.Thumbs[i].img.Source = images[i];
}
Here's my problem.
I'm loading a few BitmapImages in a BlockingCollection
public void blockingProducer(BitmapImage imgBSource)
{
if (!collection.IsAddingCompleted)
collection.Add(imgBSource);
}
the loading happens in a backgroungwork thread.
private void worker_DoWork(object sender, DoWorkEventArgs e)
{
String filepath; int imgCount = 0;
for (int i = 1; i < 10; i++)
{
imgCount++;
filepath = "Snap";
filepath += imgCount;
filepath += ".bmp";
this.Dispatcher.BeginInvoke(new Action(() =>
{
label1.Content = "Snap" + imgCount + " loaded.";
}), DispatcherPriority.Normal);
BitmapImage imgSource = new BitmapImage();
imgSource.BeginInit();
imgSource.UriSource = new Uri(filepath, UriKind.Relative);
imgSource.CacheOption = BitmapCacheOption.OnLoad;
imgSource.EndInit();
blockingProducer(imgSource);
}
}
debugging this part of the code everything looks okay, the problem comes now ...
after finishing loading the images I want to show them in UI one by one. I'm using a dispatcher to do so but I always get the message telling me that the called Thread can not access the object because it belongs to a different Thread.
public void display(BlockingCollection<BitmapImage> results)
{
foreach (BitmapImage item in collection.GetConsumingEnumerable())
{
this.Dispatcher.BeginInvoke(new Action(() =>
{
this.dstSource.Source = item;
Thread.Sleep(250);
}), DispatcherPriority.Background);
}
}
debug accuses that the error is here
this.dstSource.Source = item;
I'm trying everything but cant find out what’s wrong. Anyone has any idea?
You have to call Freeze after loading the images in order to make them accessible to other threads:
BitmapImage imgSource = new BitmapImage();
imgSource.BeginInit();
imgSource.UriSource = new Uri(filepath, UriKind.Relative);
imgSource.CacheOption = BitmapCacheOption.OnLoad;
imgSource.EndInit();
imgSource.Freeze(); // here
As far as I have understood the BitmapCacheOption.OnLoad flag, it is only effective when a BitmapImage is loaded from a stream. The Remarks section in BitmapCacheOption says:
Set the CacheOption to BitmapCacheOption.OnLoad if you wish to close a
stream used to create the BitmapImage. The default OnDemand cache
option retains access to the stream until the image is needed, and
cleanup is handled by the garbage collector.
A BitmapImage created from a Uri may be loaded asynchronously (see the IsDownloading property). Consequently, Freeze may not be callable on such a BitmapImage, as downloading may still be in progress after EndInit. I guess it nevertheless works in your case because you are loading BitmapImages from file Uris, which seems to be done immediately.
To avoid this potential problem you may just create the BitmapImage from a FileStream:
var imgSource = new BitmapImage();
using (var stream = new FileStream(filepath, FileMode.Open))
{
imgSource.BeginInit();
imgSource.StreamSource = stream;
imgSource.CacheOption = BitmapCacheOption.OnLoad;
imgSource.EndInit();
imgSource.Freeze();
}
For the further future readers, here is the code I used to fix my problem.
public void display(BlockingCollection<BitmapImage> collection)
{
if (collection.IsCompleted || collection.Count != 0)
{
BitmapImage item = collection.Take();
this.Dispatcher.BeginInvoke(new Action(() =>
{
this.dstSource.Source = item;
}), DispatcherPriority.Normal);
}
else
{
dispatcherTimer.Stop();
}
}
public void dispatcherTimer_Tick(object sender, EventArgs e)
{
display(collection);
}
public void configureDispatcherTimer()
{
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick);
TimeSpan interval = TimeSpan.FromMilliseconds(150);
dispatcherTimer.Interval = interval;
}
My application loads a lot of images in a BackgroundWorker to stay usable. My Image control is bound to a property named "ImageSource". If this is null it's loaded in the background and raised again.
public ImageSource ImageSource
{
get
{
if (imageSource != null)
{
return imageSource;
}
if (!backgroundImageLoadWorker.IsBusy)
{
backgroundImageLoadWorker.DoWork += new DoWorkEventHandler(bw_DoWork);
backgroundImageLoadWorker.RunWorkerCompleted +=
new RunWorkerCompletedEventHandler(bw_RunWorkerCompleted);
backgroundImageLoadWorker.RunWorkerAsync();
}
return imageSource;
}
}
void bw_DoWork(object sender, DoWorkEventArgs e)
{
bitmap = new BitmapImage();
bitmap.BeginInit();
try
{
bitmap.CreateOptions = BitmapCreateOptions.DelayCreation;
bitmap.DecodePixelWidth = 300;
MemoryStream memoryStream = new MemoryStream();
byte[] fileContent = File.ReadAllBytes(imagePath);
memoryStream.Write(fileContent, 0, fileContent.Length);
memoryStream.Position = 0;
bitmap.StreamSource = memoryStream;
}
finally
{
bitmap.EndInit();
}
bitmap.Freeze();
e.Result = bitmap;
}
void bw_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
BitmapSource bitmap = e.Result as BitmapSource;
if (bitmap != null)
{
Dispatcher.CurrentDispatcher.BeginInvoke(
(ThreadStart)delegate()
{
imageSource = bitmap;
RaisePropertyChanged("ImageSource");
}, DispatcherPriority.Normal);
}
}
This is all well so far but my users can change the images in question. They choose a new image in an OpenDialog, the old image file is overwritten with the new and ImageSource is raised again which loads the new image with the same filename again:
public string ImagePath
{
get { return imagePath; }
set
{
imagePath= value;
imageSource = null;
RaisePropertyChanged("ImageSource");
}
}
On some systems the overwriting of the old file results in an exception:
"a generic error occured in GDI+" and "The process cannot access the file..."
I tried a lot of things like loading with BitmapCreateOptions.IgnoreImageCache and BitmapCacheOption.OnLoad. This raised Exceptions when loading them:
Key cannot be null.
Parameter name: key
If I try this without the BackgroundWorker on the UI thread it works fine. Am I doing something wrong? Isn't it possible to load the images in the background while keeping the files unlocked?
Well, it seems all of the above works. I simplified the example for the question and somehow on the way lost the problem.
The only difference I could see in my code is that the loading of the image itself was delegated to a specific image loader class which somehow created the problem. When I removed this dependency the errors disappeared.
I have this application where I use windowsForm and UserControl to draw some diagrams. After I am done I want to save them or I want to open an existing file that I created before and keep working on the diagram. So, I want to use the save and open dialog File to save or open my diagrams.
EDIT:
this is what i have :
//save the object to the file
public bool ObjectToFile(Object model, string FileName)
{
try
{
System.IO.MemoryStream _MemoryStream = new System.IO.MemoryStream();
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter _BinaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
_BinaryFormatter.Serialize(_MemoryStream, model);
byte[] _ByteArray = _MemoryStream.ToArray();
System.IO.FileStream _FileStream = new System.IO.FileStream(FileName, System.IO.FileMode.Create, System.IO.FileAccess.Write);
_FileStream.Write(_ByteArray.ToArray(), 0, _ByteArray.Length);
_FileStream.Close();
_MemoryStream.Close();
_MemoryStream.Dispose();
_MemoryStream = null;
_ByteArray = null;
return true;
}
catch (Exception _Exception)
{
Console.WriteLine("Exception caught in process: {0}", _Exception.ToString());
}
return false;
}
//load the object from the file
public Object FileToObject(string FileName)
{
try
{
System.IO.FileStream _FileStream = new System.IO.FileStream(FileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
System.IO.BinaryReader _BinaryReader = new System.IO.BinaryReader(_FileStream);
long _TotalBytes = new System.IO.FileInfo(FileName).Length;
byte[] _ByteArray = _BinaryReader.ReadBytes((Int32)_TotalBytes);
_FileStream.Close();
_FileStream.Dispose();
_FileStream = null;
_BinaryReader.Close();
System.IO.MemoryStream _MemoryStream = new System.IO.MemoryStream(_ByteArray);
System.Runtime.Serialization.Formatters.Binary.BinaryFormatter _BinaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
_MemoryStream.Position = 0;
return _BinaryFormatter.Deserialize(_MemoryStream);
}
catch (Exception _Exception)
{
Console.WriteLine("Exception caught in process: {0}", _Exception.ToString());
}
return null;
}
and now I want to do this but it's not working
public void save()
{
SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.Filter = "txt files (*.txt)|*.txt";
saveFileDialog1.FilterIndex = 2;
saveFileDialog1.RestoreDirectory = true;
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
if (saveFileDialog1.OpenFile() != null)
{
ObjectToFile(model, saveFileDialog1.FileName);
}
}
}
but if I try without the fileDialog and i just use
ObjectToFile(model, "d:\\objects.txt");
this works. And I want to save it where I want and with my own name.
Check out the SaveFileDialog and OpenFileDialog classes. They are pretty similar, and can be used like this:
using(SaveFileDialog sfd = new SaveFileDialog()) {
sfd.Filter = "Text Files|*.txt|All Files|*.*";
if(sfd.ShowDialog() != DialogResult.OK) {
return;
}
ObjectToFile(sfd.FileName);
}
The mechanics of actually saving your file are, obviously, outside the scope of this answer.
Edit: I've updated my answer to reflect the new information in your post.