I need to save the information from an input page into a JSON File and output the information onto another page reading from the JSON File. I've tried many things and what seemed to work for me is using the specialfolder localapplication data.
Now, I don't quite understand how I can output the information and also check if the data is even put in correctly.
I previously used StreamReader to output the information on the JSON file and then put it on a ListView but this doesn't work if I have the file in the specialfolder. It says "stream cant be null". The commented out code is the code I tried in previous attempts.
Code:
ListPageVM (Read Page)
private ObservableCollection<MainModel> data;
public ObservableCollection<MainModel> Data
{
get { return data; }
set { data = value; OnPropertyChanged(); }
}
public ListPageVM()
{
var assembly = typeof(ListPageVM).GetTypeInfo().Assembly;
Stream stream = assembly.GetManifestResourceStream(Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "eintraege.json"/"SaveUp.Resources.eintraege.json"/));
//var file = Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "eintraege.json");
using (var reader = new StreamReader(stream))
{
var json = reader.ReadToEnd();
List<MainModel> dataList = JsonConvert.DeserializeObject<List<MainModel>>(json);
data = new ObservableCollection<MainModel>(dataList);
}
}
MainPageVM (Write Page)
public Command Einfügen
{
get
{
return new Command(() =>
{
// Data ins Json
_mainModels.Add(DModel);
Datum = DateTime.Now.ToString("dd.mm.yyyy");
//var assembly = typeof(ListPageVM).GetTypeInfo().Assembly;
//FileStream stream = new FileStream("SaveUp.Resources.eintraege.json", FileMode.OpenOrCreate, FileAccess.Write);
var file = Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "eintraege.json");
//Stream stream = assembly.GetManifestResourceStream("SaveUp.Resources.eintraege.json");
if (!File.Exists(file))
{
File.Create(file);
}
using (var writer = File.AppendText(file))
{
string data = JsonConvert.SerializeObject(_mainModels);
writer.WriteLine(data);
}
});
}
}
you are trying to read and write resources, not files. That won't work. Instead do this
var path = Path.Combine(System.Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "eintraege.json");
File.WriteAllText(path, myjson);
to read the data back
var json = File.ReadAllText(path);
Related
In public ScenarioPage() of ScenarioPage.cs I have the following code to read from a json file:
var assembly = typeof(ScenarioPage).GetTypeInfo().Assembly;
Stream stream = assembly.GetManifestResourceStream("firstSession.json");
using (StreamReader reader = new StreamReader(stream)) // System.ArgumentNullException
{
var json = reader.ReadToEnd();
List<SessionModel> data = JsonConvert.DeserializeObject<List<SessionModel>>(json);
foreach(SessionModel scenario in data)
{
label.Text = scenario.title;
break;
};
}
I am getting an ArgumentNullException for the stream input. firstSession.json is in the same folder as ScenarioPage.cs, and it is set as an embedded resource. It seems like Visual Studio is not recognizing that my json file is there. Is this is a bug? Or is there something wrong with my code?
Where did you put the Json File, I put it in the Json File in the root Of PCL like following screenshot.
Then use following code to read the Json File.
void GetJsonData()
{
string jsonFileName = "firstSession.json";
ContactList ObjContactList = new ContactList();
var assembly = typeof(MainPage).GetTypeInfo().Assembly;
Stream stream = assembly.GetManifestResourceStream($"{assembly.GetName().Name}.{jsonFileName}");
using (var reader = new System.IO.StreamReader(stream))
{
var jsonString = reader.ReadToEnd();
//Converting JSON Array Objects into generic list
ObjContactList = JsonConvert.DeserializeObject<ContactList>(jsonString);
}
EmployeeView.ItemsSource = ObjContactList.contacts;
}
And here is running GIF.
I update my demo to you. you can test it
https://github.com/851265601/Xamarin.Android_ListviewSelect/blob/master/PlayMusicInBack.zip
Got a bit of a strange issue with a bit of code in Xamarin Forms:
public void GetSettings()
{
var assembly = typeof(SettingsPage).GetTypeInfo().Assembly;
Stream stream = assembly.GetManifestResourceStream("FishBike_GPS.config.txt");
try
{
using (var reader = new System.IO.StreamReader(stream)) //load current settings from the config text file
{
configText = reader.ReadToEnd();
}
CurrentRentalSetting = Int32.Parse(configText);
stream.Dispose();
}
catch
{
configText = "Error reading file!";
}
}
public void SetSettings()
{
var assembly = typeof(SettingsPage).GetTypeInfo().Assembly;
Stream stream = assembly.GetManifestResourceStream("FishBike_GPS.config.txt");
try
{
using (var streamWriter = new System.IO.StreamWriter(stream)) //save current settings from the config text file
{
streamWriter.WriteLine("test");
}
stream.Dispose();
}
catch
{
configText = "Error writing to file!";
infoLabel2.Text = configText;
}
}
The read function using streamreader works perfectly fine and reads the file displaying it ect, however although I'm using the same setup for the stream the streamwriter does not. Any help would be appreciated thanks.
We have a system that stores some custom templating data in a Word document. Sometimes, updating this data causes Word to complain that the document is corrupted. When that happens, if I unzip the docx file and compare the contents to the previous version, the only difference appears to be the expected change in the customXML\item.xml file. If I re-zip the contents using 7zip, it seems to work OK (Word no longer complains that the document is corrupt).
The (simplified) code:
void CreateOrReplaceCustomXml(string filename, MyCustomData data)
{
using (var doc = WordProcessingDocument.Open(filename, true))
{
var part = GetCustomXmlParts(doc).SingleOrDefault();
if (part == null)
{
part = doc.MainDocumentPart.AddCustomXmlPart(CustomXmlPartType.CustomXml);
}
var serializer = new DataContractSerializer(typeof(MyCustomData));
using (var stream = new MemoryStream())
{
serializer.WriteObject(stream, data);
stream.Seek(0, SeekOrigin.Begin);
part.FeedData(stream);
}
}
}
IEnumerable<CustomXmlPart> GetCustomXmlParts(WordProcessingDocument doc)
{
return doc.MainDocumentPart.CustomXmlParts
.Where(part =>
{
using (var stream = doc.Package.GePart(c.Uri).GetStream())
using (var streamReader = new StreamReader(stream))
{
return streamReader.ReadToEnd().Contains("Some.Namespace");
}
});
}
Any suggestions?
Since re-zipping works, it seems the content is well-formed.
So it sounds like the zip process is at fault. So open the corrupted docx in 7-Zip, and take note of the values in the "method" column (especially for customXML\item.xml).
Compare that value to a working docx - is it the same or different? Method "Deflate" works.
I faced the same issue and it turned out it was due to encoding.
Do you already specify the same encoding when serializing/deserializing?
Couple of suggestion
a. Try doc.Package.Flush(); after you write the data back into the custom xml.
b. You may have to delete all custom part and add a new custom part. We are using the following code and it seems working fine.
public static void ReplaceCustomXML(WordprocessingDocument myDoc, string customXML)
{
MainDocumentPart mainPart = myDoc.MainDocumentPart;
mainPart.DeleteParts<CustomXmlPart>(mainPart.CustomXmlParts);
CustomXmlPart customXmlPart = mainPart.AddCustomXmlPart(CustomXmlPartType.CustomXml);
using (StreamWriter ts = new StreamWriter(customXmlPart.GetStream()))
{
ts.Write(customXML);
ts.Flush();
ts.Close();
}
}
public static MemoryStream GetCustomXmlPart(MainDocumentPart mainPart)
{
foreach (CustomXmlPart part in mainPart.CustomXmlParts)
{
using (XmlTextReader reader =
new XmlTextReader(part.GetStream(FileMode.Open, FileAccess.Read)))
{
reader.MoveToContent();
if (reader.Name.Equals("aaaa", StringComparison.OrdinalIgnoreCase))
{
string str = reader.ReadOuterXml();
byte[] byteArray = Encoding.ASCII.GetBytes(str);
MemoryStream stream = new MemoryStream(byteArray);
return stream;
}
}
}
return null; //result;
}
using (WordprocessingDocument myDoc = WordprocessingDocument.Open(ms, true))
{
StreamReader reader = new StreamReader(memStream);
string FullXML = reader.ReadToEnd();
ReplaceCustomXML(myDoc, FullXML);
myDoc.Package.Flush();
//Code to save file
}
I'm trying to create a resx file and write it to a stream so that I might return it as a string instead of immediately saving it to a file. However, when I try to read that stream, it is empty. What am I doing wrong here? i did verify that the entries are not null. I can actually use the ResXResourceWriter constructor that saves it to disk successfully, but I'm trying to avoid using temp files. Also, I can see the stream is 0k before the loop and about 8k in length after the loop.
using (var stream = new MemoryStream())
{
using (var resx = new ResXResourceWriter(stream))
{
// build the resx and write to memory
foreach (var entry in InputFile.Entries.Values)
{
resx.AddResource(new ResXDataNode(entry.Key, entry.Value) { Comment = entry.Comment });
}
var reader = new StreamReader(stream);
var text = reader.ReadToEnd(); // text is an empty string here!
return null;
}
}
You need to flush and reset the output/stream before trying to read it. This should work, using Generate and Position:
resx.Generate();
stream.Position = 0;
var reader = new StreamReader(stream);
var text = reader.ReadToEnd();
return text;
The following unit test fails:
[TestMethod]
public void Add_file_to_blob_and_retrieve_it()
{
var blobName = Guid.NewGuid().ToString();
var testFileContents = File.ReadAllText(TestFileSpec);
Trace.WriteLine(string.Format("Opening blob container {0}", UnitTestBlobAgentName));
CloudStorageAccount.SetConfigurationSettingPublisher(
(configName, configSetter) => configSetter(ConfigurationManager.AppSettings[configName]));
var cloudStorage = CloudStorageAccount.FromConfigurationSetting("StorageConnectionString");
var blobClient = cloudStorage.CreateCloudBlobClient();
var container = blobClient.GetContainerReference(UnitTestBlobAgentName.ToLower());
try
{
Trace.WriteLine(string.Format("Uploading file {0}", TestFileSpec));
var blob = container.GetBlobReference(blobName);
blob.UploadFile(TestFileSpec);
blob.Properties.ContentType = "ByteArray";
blob.SetProperties();
var blob1 = container.GetBlobReference(blobName);
var found = blob1.DownloadText();
Assert.AreEqual(testFileContents.Trim(), found.Trim());
}
finally
{
if (null != container)
{
Trace.WriteLine(string.Format("Deleting blob {0}", blobName));
var blob2 = container.GetBlobReference(blobName);
blob2.DeleteIfExists(new BlobRequestOptions { DeleteSnapshotsOption = DeleteSnapshotsOption.IncludeSnapshots });
}
}
}
It turns out, the returned string begins with the dword 0xFEFF (the Unicode BOM). I've traced through the Microsoft debug symbols, and the BOM exists in the return stream. AFAICT, it comes from the HttpResponse.GetResponseStream() method call way down in the Microsoft.WindowsAzure.StorageClient.CloudBlob class.
What's the best way to ensure that the input and output are identical? Ensure the input is converted to Unicode before going in? Strip the BOM from the output? Any other ideas?
This is an old one, but if your blob is encoded as Unicode in azure, and you want to download it to a text string, this code will do the trick. Just keep in mind, the weakness here is that you've got to allocate the memory twice. If there's a more efficient way of getting to a Unicode string (synchronously, anyway,) I couldn't find it.
string fileText;
using (var memoryStream = new MemoryStream())
{
cloudBlob.DownloadToStream(memoryStream);
memoryStream.Position = 0;
using (var reader = new StreamReader(memoryStream, Encoding.Unicode))
{
fileText = reader.ReadToEnd();
}
}