I have a text file with a list of 300,000 words and the frequency with wich they occur. Each line is in the format Word:FequencyOfOccurence.
I want this information to be accessible from within the C# code. I can't hard code the list since it is too long, and I'm not sure how to go about accessing it from a file on the server. Ideally I'd ideally like the information to be downloaded only if it's used (To save on bandwidth) but this is not a high priority as the file is not too big and internet speeds are always increasing.
It doesn't need to be useable for binding.
The information does not need to be editable once the project has been built.
Here is another alternative. Zip the file up and stick it in the clientBin folder next to the apllication XAP. Then at the point in the app where the content is needed do something like this:-
public void GetWordFrequencyResource(Action<string> callback)
{
WebClient client = new WebClient();
client.OpenReadAsync += (s, args) =>
{
try
{
var zipRes = new StreamResourceInfo(args.Result, null)
var txtRes = Application.GetResourceStream(zipRes, new Uri("WordFrequency.txt", UriKind.Relative));
string result = new StreamReader(txtRes.Stream).ReadToEnd();
callback(result);
}
catch
{
callback(null); //Fetch failed.
}
}
client.OpenReadAsync(new Uri("WordFrequency.zip", UriKind.Relative"));
}
Usage:-
var wordFrequency = new Dictionary<string, int>();
GetWordFrequencyResource(s =>
{
// Code here to burst string into dictionary.
});
// Note code here is asynchronous with the building of the dictionary don't attempt to
// use the dictionary here.
The above code allows you to store the file in an efficient zip format but not in the XAP itself. Hence you can download it on demand. It makes use of the fact that a XAP is a zip file so Application.GetResourceStream which is designed to pull resources from XAP files can be used on a zip file.
BTW, I'm not actually suggesting you use a dictionary, I'm just using a dictionary as simple example. In reality I would imagine the file is in sorted order. If that is the case you could use a KeyValuePair<string, int> for each entry but create a custom collection type that holds them in an array or List and then use some Binary search methods to index into it.
Based on your comments, you could download the word list file if you are required to have a very thin server layer. The XAP file containing your Silverlight application is nothing more than a ZIP file with all the referenced files for your Silverlight client layer. Try adding the word list as content that gets compiled into the XAP and see how big the file gets. Text usually compresses really well. In general, though, you'll want to be friendly with your users in how much memory your application consumes. Loading a huge text file into memory, in addition to everything else you need in your app, may untimately make your app a resource hog.
A better practice, in general, would be to call a web service. The service could would perform whatever look up logic you need. Here's a blog post from a quick search that should get you started: (This was written for SL2, but should apply the same for SL3.)
Calling web services with Silverlight 2
Even better would be to store your list in a SQL Server. It will be much easier and quicker to query.
You could create a WCF service on the server side that will send the data to the Silverlight application. Once you retrieve the information you could cache it in-memory inside the client. Here's an example of calling a WCF service method from Silverlight.
Another possibility is to embed the text file into the Silverlight assembly that is deployed to the client:
using (var stream = Assembly.GetExecutingAssembly()
.GetManifestResourceStream("namespace.data.txt"))
using (var reader = new StreamReader(stream))
{
string data = reader.ReadToEnd();
// Do something with the data
}
Related
So, the title may be misleading. I am building an android app that reads information from a text file, which is located on a cloud server (I would prefer to use either OneDrive, DropBox, or Google Drive [whichever is easiest]; others are fine). Periodically, the program will write information to the text file, still located on the cloud server. So, my question is twofold: Is it possible to read and write to a text file that is located on a cloud server? If so, how in the world would I complete this task? I have noticed the use of WebClient but I can't find a reasonable method or explanation on how this works. This program is coded in C#. This is what I have so far:
private string filename = "datafile.txt";
private List<Category> myList; //A list of an object that I developed ('Category')
//Allow the user interface to handle the error
public void readDatabase() {
//Here is where the magic has to occur, in order to read the file
...
//The usual reader that I use to read standard text files
StreamReader fileReader = new StreamReader(filename);
string line = "";
while ((line = fileReader.ReadLine()) != null)
//convertToCategory is my private method to convert the string to
myLine.Add(convertToCategory(line);
fileReader.close();
}
public void writeDatabase() {
//Here is where the magic has to occur, in order to write to the file
...
//The usual writer that I use to write standard text files
StreamWriter fileWriter = new StreamWriter(filename);
for (int i = 0; i < this.myList.Count; i++)
//toString() is something was developed in my object called 'Category'
fileWriter.WriteLine(fileWriter[i].toString());
fileWriter.close();
}
I would love to use Google Drive as my cloud server, but I am open to other possibilities, if necessary. I just want an easy and efficient method to read/write to the text file.
Possible Implementations:
Have seen possible solutions, where the file is downloaded locally and then read like normal and then uploaded at time of closing. However, if I could get away with it, I don't want the text file to be downloaded.
I have, also, seen several places where a SQL database is used in this instance. But the unfortunate thing is that I don't have any knowledge in developing with SQL. So, using a SQL server would be ideal (because speed is very important for this application) but it will be difficult for me to understand how it works.
I have an issue with a class library; I am preparing a library with an interface that represents a specific data storage signature. The purpose is to use the interface as a basis for implementing a number of specific classes storing configuration information in different formats (text files, xml files, etc.) while retaining the same usage profile to the application using it. I have a problem, though. In this case I am trying to embed an xml file as a resource - this file is one type of format to store configuration data. The file is located as an embedded resource in a subfolder to the project, as shown in the attached illustration.
In the following code snippet it is shown how I have implemented the functionality until now.
public ConfigInfoXmlSource()
{
if (!string.IsNullOrEmpty(Settings.Default.CurrentConfigFile))
FileNameAndPath = Settings.Default.CurrentConfigFile;
else
FileNameAndPath = DefaultConfigFileName + DefaultFileExtension;
// Prepare XML.
System.Reflection.Assembly a = Assembly.GetExecutingAssembly();
XmlDocument doc = new XmlDocument();
Stream manifestResourceStream =
a.GetManifestResourceStream("TestTool.Config.Config1.xml");
if (manifestResourceStream == null)
{
// ???
}
...
doc.Load(manifestResourceStream);
...
}
In the section marked "Prepare XML" I am trying to read a stream from the embedded resource. After the reading, it is tested whether a stream was indeed created. If the file is found, the manifestResourceStream will contain the xml data - so far so good. The problem arises if the file for some reason has been accidentally deleted - in that case I want to create a new file as an embedded resource to replace the deleted file. That is supposed to happen in the conditional in the part shown as "???".
I have tried everything I could think of, searched Google for answers, etc. - to no avail.
Does anyone have a clue to how this is accomplished? Any help will be greatly appreciated.
Thanks in advance.
Best regards.
If you have a embedded resource,it is built into your binaries.It is not an physical file,rather something which is present inside the built file(dll in this case).So,once it is included,I do not think it can ever be deleted. As per my knowledge embedded resource can only be set while building your project binaries and you can not explicitly do it at runtime as it is not needed due to reasons mentioned above.
I have a .txt file that i process into a List in my program.
I would like to somehow save that List and include it in the program itself so that it loads every time the program starts, so I don't have to process it every time from a .txt file.
Its more complicated than just "int x = 3;" cause it has like 10k lines and I don't wanna copy paste all that in the beginning.
I've looked all over but haven't found anything similar, any ideas guys?
Also if thee's a solution, can it work with any type (arrays, Dictionaries)?
As requested, the code is:
var text = System.IO.File.ReadAllText(#"C:\Users\jazz7\Desktop\links_zg.txt");
EDIT
Joe suggested the solution:
Included the file within the project, set its "build action" to embedded resource in Properties and used this code:
private string linkovi = "";
...
var assembly = Assembly.GetExecutingAssembly();
var resourceName = "WindowsFormsApplication4.links_zg.txt";
using (Stream stream = assembly.GetManifestResourceStream(resourceName))
using (StreamReader reader = new StreamReader(stream))
{
linkovi = reader.ReadToEnd();
}
string linkovi now contains the txt file and is now within the application. Thanks all!
You could store the file as a resource in your executable file.
This KB article describes how to do it.
Fundamentally, youve got to choose between storing your data in memory or storing it on the hard drive. The former will cut your loading time, but might use an unacceptable amount of memory, whilst the latter is slower, as youve identified. Either way, your data has to be stored somewhere.
Do you need to load all of the data at once? If the loading time is the issue, you could process the file line by line. While this would be slower overall, you would still have access to some usable data sooner.
I'm working on an UWP application where a user can input data which is placed in a listview. All fine and dandy, but how can I save the user data to a separate file and load it the next time a user boots up the app?
I've tried to find a solution, but I had great difficulty to understand these code snippets and on how to apply these (since I'm fairly new to C# and App development). Would somebody like to explain how I can achieve the saving/loading of the data and explain what the code does?
Thanks in advance! :)
You can create a file like this:
StorageFile ageFile = await local.CreateFileAsync("Age.txt", CreationCollisionOption.FailIfExists);
I can read and write to a file like this:
StorageFolder local = Windows.Storage.ApplicationData.Current.LocalFolder;
var ageFile = await local.OpenStreamForReadAsync(#"Age.txt");
// Read the data.
using (StreamReader streamReader = new StreamReader(ageFile))
{
//Use like a normal streamReader
}
if you are trying to write, use OpenStreamForWriteAsync;
If I understood well, you have some kind of object structure that serves as a model for your ListView. When the application is started, you want to read a file where the data is present. When closing the application (or some other event) write the file with the changes done. Right?
1) When your application is loaded / closed (or upon modifications or some event of your choice), use the Windows.Storage API to read / write the text into the file.
2) If the data you want to write is just a liste of strings, you can save this as is in the file. If it is more complicated, I would recommend serializing it in JSON format. Use JSON.NET to serialize (object -> string) and deserialize (object <- string) the content of your file and object structure.
Product product = new Product();
product.Name = "Apple";
...
string json = JsonConvert.SerializeObject(product);
I have a class in my Silverlight app that (de-)serializes JSON strings to/from an object class.
I use WebClient.OpenReadAsync to get a file that contains this JSON string:
{"FirstName":"Bob","LastName":"Underwood"}
After calling OpenReadAsync however, the retrieved string has a lot of extra characters:
"PK\n\0\0\0\0\0�u�>h��5\0\0\05\0\0\0\t\0\0\0test.json\"{\\\"FirstName\\\":\\\"Gary\\\",\\\"LastName\\\":\\\"MacDonald\\\"}\"PK\0\n\0\0\0\0\0�u�>h��5\0\0\05\0\0\0\t\0\0\0\0\0\0\0\0\0 \0\0\0\0\0\0\0test.jsonPK\0\0\0\0\0\07\0\0\0\\\0\0\0\0\0"
This is the code I'm using to download the JSON:
WebClient client = new WebClient();
client.OpenReadCompleted += client_OpenReadCompleted;
client.OpenReadAsync(new Uri("/someJsonFile.zip", UriKind.Relative));
void client_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e) {
if (e.Error == null) {
StreamReader reader = new StreamReader(e.Result);
string jsonString = reader.ReadToEnd().ToString();
}
else {
addMessage("Error " + e.Error.ToString());
}
}
jsonString ends up with all that extra data, so I can't deserialize it as is.
Another thing to note: the URI points to someJsonFile.zip, but it's really not zipped, when I give the file a extension like .json, or no extension, I get a error that it cannot find the file, but when I give it a extension like .zip, it finds it fine. Is there a way I can use a normal or no extension? I was wondering if this was a configuration issue.
Questions:
Am I doing something wrong in pulling this file and using StreamReader to get the string that's causing me to get all that trash data?
Do I need to do something specific to be able to use WebClient to grab a file with different extensions, like .json, or even no extension at all?
1 - That data stream certainly is a ZIP (PK is the old PKZip marker and the test.json filename is mentioned in its index as well).
Your server may be setup to serve all files compressed (or you may simply be accessing an actual zip file). Please check the server settings.
2 - As for the second question, the WebClient does not care about file types. It is just a stream of data that needs to be interpreted by something that knows what the data is (i.e. your code).
It is only the server that may be configured to serve up different files in different ways.
I was able to figure things out with my domain provider, appears to have been some configuration issues on their end.