Search Results

Search found 3040 results on 122 pages for 'saveing saving'.

Page 98/122 | < Previous Page | 94 95 96 97 98 99 100 101 102 103 104 105  | Next Page >

• File based caching under PHP

  - by azatoth

  I've been using http://code.google.com/p/phpbrowscap/ for a project, and it usually works nice. But a few times it's cache, which is plain php-files (see http://code.google.com/p/phpbrowscap/source/browse/trunk/browscap/Browscap.php#372 et. al.), has been "zeroed", i.e. the whole cache file has become large blob of NULLs. Instead of trying to find out why the files become NULL, I though perhaps it might be better to change the caching strategy to something more resilient. So I do wonder if you has any good ideas what would be a good solution; I've been looking at http://www.jongales.com/blog/2009/02/18/simple-file-based-php-cache-class/ and http://www.phpclasses.org/package/313-PHP-Cache-arbitrary-data-in-files-.html and I also though of just saving an serialized array to the file instead of pure php as it's been doing now; But I'm uncertain what approach I should target here. I'm grateful for any insight into this area of technology, as I know it's complex from a performance point of view.

  Read the article

• how to check null value of Integer type field in ASP.NET MVC view?

  - by Vikas

  Hi, I have integer type field in database which is having property "Not Null". when i create a view & do a validation, if i left that field blank, it will consider it as 0 so i can not compare it with 0 because if someone insert a value 0 then it will be considered as error! one another problem is that i am using Model error as described in the book "ASP.NET MVC 1.0" @ Scott Gu blog. And I am checking the value in partial class of object (created by LINQ-To-SQL). i.e public partial class Person { public bool IsValid { get { return (GetRuleViolations().Count() == 0); } } public IEnumerable<RuleViolation> GetRuleViolations() { if (String.IsNullOrEmpty(Name)) yield return new RuleViolation("Name is Required", "Name"); if (Age == 0) yield return new RuleViolation("Age is Required", "Age"); yield break; } partial void OnValidate(ChangeAction action) { if (!IsValid) throw new ApplicationException("Rule violations prevent saving"); } } There is also problem with range. Like in database if i declared as smallint i.e. short in c#, now if i exceed that range then it gives error as "A Value is reguired". so finally is there any best way for validation in ASP.NET MVC?

  Read the article

• Detaching all entities of T to get fresh data

  - by Goran

  Lets take an example where there are two type of entites loaded: Product and Category, Product.CategoryId - Category.Id. We have available CRUD operations on products (not Categories). If on another screen Categories are updated (or from another user in the network), we would like to be able to reload the Categories, while preserving the context we currently use, since we could be in the middle of editing data, and we do not want changes to be lost (and we cannot depend on saving, since we have incomplete data). Since there is no easy way to tell EF to get fresh data (added, removed and modified), we thought of twp possible ways: 1) Getting products attached to context, and categories detached from context. This would mean that we loose the ability to access Product.Category.Name, which we do sometimes require, so we would need to manually resolve it (example when printing data). 2) detaching / attaching all Categories from current context. Context.ChangeTracker.Entries().Where(x => x.Entity.GetType() == typeof(T)).ForEach(x => x.State = EntityState.Detached); And then reload the categories, which will get fresh data. Do you find any problem with this second approach? We understand that this will require all constraints to be put on foreign keys, and not navigation properties, since when detaching all Categories, Product.Category navigation properties would be reset to null also. Also, there could be a potential performance problem, which we did not test, since there could be couple of thousand products loaded, and all would need to resolve navigation property when reloading. Which of the two do you prefer, and is there a better way (EF6 + .NET 4.0)?

  Read the article

• c++ issues with cin.fail() in my program

  - by Wallace

  I want to use input y to do saving thing,and r to do resuming, but then i write it in the following codes,and then I input y or r,I just to be noticed ""Please enter two positve numbers" this line code "if(x==(int)('y'))"and next line is ignored.how could this happen int main(){ cout<<"It's player_"<<player+1<<"'s turn please input a row and col,to save and exit,input 0,resume game input"<<endl; while(true){ cin>>x; if(x==(int)('y')) {save();has_saved=true;break;} if(x==(int)('r')) {resume();has_resumed=true;break;} cin>>y; if(cin.fail()){ cout<<"Please enter two positve numbers"<<endl; cin.clear(); cin.sync();} else if (x>n||x<1||y<1||y>n) { cout<<"your must input a positive number less or equal than "<<n<<endl; continue;} else if(chessboard[x][y]!=' ') {cout<<"Wrong input please try again!"<<endl; continue;} else { chessboard[x][y]=player_symbol[player+1]; break; } } }

  Read the article

• In .NET, how do I prevent, or handle, tampering with form data of disabled fields before submission?

  - by David

  Hi, If a disabled drop-down list is dynamically rendered to the page, it is still possible to use Firebug, or another tool, to tamper with the submitted value, and to remove the "disabled" HTML attribute. This code: protected override void OnLoad(EventArgs e) { var ddlTest = new DropDownList() {ID="ddlTest", Enabled = false}; ddlTest.Items.AddRange(new [] { new ListItem("Please select", ""), new ListItem("test 1", "1"), new ListItem("test 2", "2") }); Controls.Add(ddlTest); } results in this HTML being rendered: <select disabled="disabled" id="Properties_ddlTest" name="Properties$ddlTest"> <option value="" selected="selected">Please select</option> <option value="1">test 1</option> <option value="2">test 2</option> </select> The problem occurs when I use Firebug to remove the "disabled" attribute, and to change the selected option. On submission of the form, and re-creation of the field, the newly generated control has the correct value by the end of OnLoad, but by OnPreRender, it has assumed the identity of the submitted control and has been given the submitted form value. .NET seems to have no way of detecting the fact that the field was originally created in a disabled state and that the submitted value was faked. This is understandable, as there could be legitimate, client-side functionality that would allow the disabled attribute to be removed. Is there some way, other than a brute force approach, of detecting that this field's value should not have been changed? I see the brute force approach as being something crap, like saving the correct value somewhere while still in OnLoad, and restoring the value in the OnPreRender. As some fields have dependencies on others, that would be unacceptable to me.

  Read the article

• Parameter cannot be null error after success save

  - by tigermain

  I am getting the following nhibernate error when saving an entity (via: NHibernateSession.Save(entity);) despite it being persisted to the database fine "Value cannot be null.\r\nParameter name: id" This is my hbm file <?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="JeanieMaster.Domain.Entities" assembly="JeanieMaster.Domain"> <class name="ActionLog" table="ActionLog" schema="[DBSVR1].[mydatabase].[dbo]" select-before-update="false" optimistic-lock="none"> <id name="Id" column="ActionLogId" type="Int32"> <generator class="identity"/> </id> <property name="ActionId" type="Int32"/> <many-to-one name="User" class="JeanieUser" column="UserId" /> <many-to-one name="ApplicationProvider" class="ApplicationProvider" column="ApplicationProviderId" /> <many-to-one name="ContentProvider" class="ContentProvider" column="ContentProviderId" /> <many-to-one name="SearchLog" class="SearchLog" column="SearchLogId" /> <property name="Data" type="string"/> <property name="DateCreated" type="DateTime"/> <property name="ActionDuration" type="Double"/> </class> </hibernate-mapping>

  Read the article

• Editable, growable DataGrid that retains values on postback and updates underlying DataTable

  - by jlstrecker

  I'm trying to create an ASP.NET/C# page that allows the user to edit a table of data, add rows to it, and save the data back to the database. For the table of data, I'm using a DataGrid whose cells contain TextBoxes or CheckBoxes. I have a button for adding rows (which works) and a button for saving the data. However, I'm quite stuck on two things: The TextBoxes and CheckBoxes should retain their values on postback. So if the user edits a TextBox and clicks the button to add more rows, the edits should be retained when the page reloads. However, the edits should not be saved to the database at this point. When the user clicks the save button, or anytime before, the DataTable underlying the DataGrid needs to be updated with the values of the TextBoxes and CheckBoxes so that the DataTable can be sent to the database. I have a method that does this, but I can't figure out when to call it. Any help getting this to work, or suggestions of alternative user interfaces that would behave similarly, would be appreciated.

  Read the article

• Firefox extension: How to inject javascript into page and run it?

  - by el griz

  I'm writing a Firefox extension to allow users to annotate any page with text and/or drawings and then save an image of the page including the annotations. Use cases would be clients reviewing web pages, adding feedback to the page, saving the image of this and emailing it back to the web developer or testers taking annotated screenshots of GUI bugs etc. I wrote the annotation/drawing functionality in javascript before developing the extension. This script adds a <canvas> element to the page to draw upon as well as a toolbar (in a <div>) that contains buttons (each <canvas> elements) for the different draw tools e.g. line, box, ellipse, text, etc. This works fine when manually included in a page. I now need a way for the extension to: Inject this script into any page including pages I don't control. This needs to occur when the user invokes the extension, which can be after the page has loaded. Once injected the init() function in this script that adds the canvas and toolbar elements etc. needs to be run somehow, but I can't determine how to call this from the extension. Note that once injected I don't need this script to interact with the extension (as the extension just takes a screenshot of the entire document (and removes the added page elements) when the user presses the save button in the extension chrome).

  Read the article

• Is NSManagedObjectContext autosaved or am I looking at NSFetchedResultsController's cache?

  - by Andreas

  I'm developing an iPhone app where I use a NSFetchedResultsController in the main table view controller. I create it like this in the viewDidload of the main table view controller: NSSortDescriptor *sortDescriptorDate = [[NSSortDescriptor alloc] initWithKey:@"date" ascending:YES]; NSSortDescriptor *sortDescriptorTime = [[NSSortDescriptor alloc] initWithKey:@"start" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptorDate,sortDescriptorTime, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; [sortDescriptorDate release]; [sortDescriptorTime release]; [sortDescriptors release]; controller = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:context sectionNameKeyPath:@"date" cacheName:nil]; [fetchRequest release]; NSError *error; BOOL success = [controller performFetch:&error]; Then, in a subsequent view, I create a new object on the context: TestObject *testObject = [NSEntityDescription insertNewObjectForEntityForName:@"TestObject" inManagedObjectContext:context]; The TestObject has several related object which I create in the same way and add to the testObject using the provided add...Objects methods. Then, if before saving the context, I press cancel and go back to the main table view, nothing is shown as expected. However, if I restart the app, the object I created on the context shows in the main table view. How come? At first, I thought it was because the NSFetchedResultsController was reading from the cache, but as you can see I set this to nil just to test. Also, [context hasChanges] returns true after I restart. What am I missing here?

  Read the article

• Storing float numbers as strings in android database

  - by sandis

  So I have an app where I put arbitrary strings in a database and later extract them like this: Cursor DBresult = myDatabase.query(false, Constant.DATABASE_NOTES_TABLE_NAME, new String[] {"myStuff"}, where, null, null, null, null, null); DBresult.getString(0); This works fine in all cases except for when the string looks like a float number, for example "221.123123123". After saving it to the database I can extract the database to my computer and look inside it with a DB-viewer, and the saved number is correct. However, when using cursor.getString() the string "221.123" is returned. I cant for the life of me understand how I can prevent this. I guess I could do a cursor.getDouble() on every single string to see if this gives a better result, but that feels sooo ugly and inefficient. Any suggestions? Cheers, edit: I just made a small test program. This program prints "result: 123.123", when I would like it to print "result: 123.123123123" SQLiteDatabase database = openOrCreateDatabase("databas", Context.MODE_PRIVATE, null); database.execSQL("create table if not exists tabell (nyckel string primary key);"); ContentValues value = new ContentValues(); value.put("nyckel", "123.123123123"); database.insert("tabell", null, value); Cursor result = database.query("tabell", new String[]{"nyckel"}, null, null, null, null, null); result.moveToFirst(); Log.d("TAG","result: " + result.getString(0));

  Read the article

• NHibernate. DTO -> Domain

  - by Andrew Kalashnikov

  Hello guys. I've got SOA which processing data for diff clients(asp,sl). The base of this design is domains of my business model. For transporting,showing it to clients I use DTO. For mapping domain to DTO I use AutoMapper. Now I should persist new entities from clients. I want use my DTO's at this scenario too. So i've got some questions as I'm not much familiar with this design 1) Is it a good practice build DTO on client and send it to web-service on the wire? MayBe i should pass my domains? 2) Is it possible have several DTO's to one domain (one show at grid, and one to save). For saving I need set all nonprimitive props at client. 3) DTO - to Domain. If I've got int can I use AutoMapper to generate NHibernate Proxy for this ID, or I should do i manually. Your expierence and practice are very interesting. Thanks for answer!!!

  Read the article

• ASP.NET: ModalPopupExtender prevents button click event from firing

  - by C. Griffin

  Here is what I'm trying to do: Click a button on my page, which in turn makes (2) things happen: Display a ModalPopup to prevent the user from pressing any buttons or changing values Call my code behind method, hiding the ModalPopup when finished Here is the ASP markup: <asp:UpdatePanel ID="UpdatePanel2" runat="server" ChildrenAsTriggers="true" UpdateMode="Always"> <Triggers> <asp:AsyncPostBackTrigger ControlID="btnSaveData" EventName="Click" /> </Triggers> <ContentTemplate> <asp:Panel ID="pnlHidden" runat="server" style="display: none;"> <div> <h1>Saving...</h1> </div> </asp:Panel> <cc1:ModalPopupExtender ID="modalPopup" BackgroundCssClass="modalBackground" runat="server" TargetControlID="btnSaveData" PopupControlID="pnlHidden"> </cc1:ModalPopupExtender> <asp:Button ID="btnSaveData" runat="server" Text="Save Data" OnClick="btnSaveData_Click" /> </ContentTemplate> </asp:UpdatePanel> Now, here is my code behind C# code: protected void btnSaveData_Click(object sender, EventArgs e) { UpdateUserData(GetLoggedInUser()); modalPopup.Enabled = false; } Why doesn't this work? The ModalPopup displays perfectly, but the btnSaveData_Click event NEVER fires.

  Read the article

• Dockable panes created in CChildFrame not visible the second time the app. starts.

  - by Nijenhuis

  Hi, I have created some dockable panes in CChildFrame::OnCreate() The first time i start the application they are shown. The second time i start the application they are created but the splitterwindows are completly against the sides of the clients area (bottom and right), so not visible. So i have to use the mouse to pull the splitters into the clientarea so that the dockable windows become visible again. If i do File-New in my app a new client window is created and showing the dockable windows as they should be. I Think this has something to do with saving the windows layout in the registry, because if i change SetRegistryKey(_T("61sakjgsajkdg")); in the CWinApp derived class of my app. and rerun they are shown again the first time. (but not the second time i restart the app). How can i save the layout of those dockable windows as well, so if i restart my app. they are visible ? Or else how do i prevent my app. of overwritting the window layout with the one previously saved. Something to do with LoadCustomState() and SaveCustomState() ?, i could no find any info on howto implement those methods. I have here a link to the demo project to demonstrate what i mean: http://www.4shared.com/file/237193472/c384f0f6/GUI60.html Could someone tell me how to show those dockable windows in my CChildFrame class the second time the app starts?

  Read the article

• Micro Second resolution timestamps on windows.

  - by Nikhil

  How to get micro second resolution timestamps on windows? I am loking for something better than QueryPerformanceCounter, QueryPerformanceFrequency (these can only give you an elapsed time since boot, and are not necessarily accurate if they are called on different threads - ie QueryPerformanceCounter may return different results on different CPUs. There are also some processors that adjust their frequency for power saving, which apparently isn't always reflected in their QueryPerformanceFrequency result.) There is this, http://msdn.microsoft.com/en-us/magazine/cc163996.aspx but it does not seem to be solid. This looks great but its not available for download any more. http://www.ibm.com/developerworks/library/i-seconds/ This is another resource. http://www.lochan.org/2005/keith-cl/useful/win32time.html But requires a number of steps, running a helper program plus some init stuff also, I am not sure if it works on multiple CPUs Also looked at the Wikipedia link on the subject which is interesting but not that useful. http://en.wikipedia.org/wiki/Time_Stamp_Counter If the answer is just do this with BSD or Linux, its a lot easier thats fine, but I would like to confirm this and get some explanation as to why this is so hard in windows and so easy in linux and bsd. Its the same damm hardware...

  Read the article

• response.write only working IE for ASP.NET

  - by slowlycooked

  I'm using uploadify (http://www.uploadify.com/) to upload video to my site then convert them into *.flv using ffmpeg and play preview. But it dosen't fully working with firefox, chrome or safari. uploadify provides a onComplete interface, so when the script (.ashx, .php) used on your site for saving uploaded files. you can use response.write("blabla") or (echo "blabla") to invoke the javascript function that registed as OnComplete. i have test with few video files like avi, mpg, mp4, they are less then 50mb,and they all worked with all 4 browsers. However, when i was trying to upload a 75mb mp4 file, it worked in IE, but didn't working in other three. I can see the .flv file has been create in the upload folder, i can see debug messsage output after response.write("blabla"), but the javascript function was not invoked. i.e. the preview didn't play. anyone knows why? is there a timeout or something on response.write so after a period of time it wont work? e.g. 75mb file took longer time to convert than other smaller size file i tried. thansk

  Read the article

• Should a Trim method generally in the Data Access Layer or with in the Domain Layer?

  - by jpierson

  I'm dealing with a database that contains data with inconsistencies such as white leading and trailing white space. In general I see a lot of developers practice defensive coding by trimming almost all strings that come from the database that may have been entered by a user at some point. In my oppinoin it is better to do such formating before data is persisted so that it is done only once and then the data can be in a consistent and reliable state. Unfortunatley this is not the case however which leads me to the next best solution, using a Trim method. If I trim all data as part of my data access layer then I don't have to concern myself with defensive trimming within the business objects of my domain layer. If I instead put the trimming responsibility in my business objects, such as with set accessors of my C# properties, I should get the same net results however the trim will be operating on all values assigned to my business objects properties not just the ones that come from the inconsistent database. I guess as a somewhat philisophical question that may determine the answer I could ask "Should the domain later be responsible for defensive/coercive formatting of data?" Would it make sense to have a set accessor for a PhoneNumber property on a business object accept a unformatted or formatted string and then attempt to format it as required or should this responsibility be pushed to the presentation and data access layers leaving the domain layer more strict in the type of data that it will accept? I think this may be the more fundamental question. Update: Below are a few links that I thought I should share about the topic of data cleansing. Information service patterns, Part 3: Data cleansing pattern LINQ to SQL - Format a string before saving? How to trim values using Linq to Sql?

  Read the article

• Implementing list position locator in C++?

  - by jfrazier

  I am writing a basic Graph API in C++ (I know libraries already exist, but I am doing it for the practice/experience). The structure is basically that of an adjacency list representation. So there are Vertex objects and Edge objects, and the Graph class contains: list<Vertex *> vertexList list<Edge *> edgeList Each Edge object has two Vertex* members representing its endpoints, and each Vertex object has a list of Edge* members representing the edges incident to the Vertex. All this is quite standard, but here is my problem. I want to be able to implement deletion of Edges and Vertices in constant time, so for example each Vertex object should have a Locator member that points to the position of its Vertex* in the vertexList. The way I first implemented this was by saving a list::iterator, as follows: vertexList.push_back(v); v->locator = --vertexList.end(); Then if I need to delete this vertex later, then rather than searching the whole vertexList for its pointer, I can call: vertexList.erase(v->locator); This works fine at first, but it seems that if enough changes (deletions) are made to the list, the iterators will become out-of-date and I get all sorts of iterator errors at runtime. This seems strange for a linked list, because it doesn't seem like you should ever need to re-allocate the remaining members of the list after deletions, but maybe the STL does this to optimize by keeping memory somewhat contiguous? In any case, I would appreciate it if anyone has any insight as to why this happens. Is there a standard way in C++ to implement a locator that will keep track of an element's position in a list without becoming obsolete? Much thanks, Jeff

  Read the article

• 'Fixed' for loop - what is more efficient?

  - by pimvdb

  I'm creating a tic-tac-toe game, and one of the functions has to iterate through each of the 9 fields (tic-tac-toe is played on a 3x3 grid). I was wondering what is more efficient (which one is perhaps faster, or what is the preferred way of scripting in such situation) - using two for nested loops like this: for(var i=0; i<3; i++) { for(var j=0; j<3; j++) { checkField(i, j); } } or hard-coding it like this: checkField(0, 0); checkField(0, 1); checkField(0, 2); checkField(1, 0); checkField(1, 1); checkField(1, 2); checkField(2, 0); checkField(2, 1); checkField(2, 2); As there are only 9 combinations, it would be perhaps overkill to use two nested for loops, but then again this is clearer to read. The for loop, however, will increment variables and check whether i and j are smaller than 3 every time as well. In this example, the time saving at least might be negligible, but what is the preferred way of coding in this case? Thanks.

  Read the article

• Drawbacks with using Class Methods in Objective C.

  - by RickiG

  Hi I was wondering if there are any memory/performance drawbacks, or just drawbacks in general, with using Class Methods like: + (void)myClassMethod:(NSString *)param { // much to be done... } or + (NSArray*)myClassMethod:(NSString *)param { // much to be done... return [NSArray autorelease]; } It is convenient placing a lot of functionality in Class Methods, especially in an environment where I have to deal with memory management(iPhone), but there is usually a catch when something is convenient? An example could be a thought up Web Service that consisted of a lot of classes with very simple functionality. i.e. TomorrowsXMLResults; TodaysXMLResults; YesterdaysXMLResults; MondaysXMLResults; TuesdaysXMLResults; . . . n I collect a ton of these in my Web Service Class and just instantiate the web service class and let methods on this class call Class Methods on the 'Results' Classes. The classes are simple but they handle large amount of Xml, instantiate lots of objects etc. I guess I am asking if Class Methods lives or are treated different on the stack and in memory than messages to instantiated objects? Or are they just instantiated and pulled down again behind the scenes and thus, just a way of saving a few lines of code?

  Read the article

• Increasing figure size in Matplotlib

  - by Anirudh

  I am trying to plot a graph from a distance matrix. The code words fine and gives me a image in 800 * 600 pixels. The image being too small, All the nodes are packed together. I want increase the size of the image. so I added the following line to my code - figure(num=None, figsize=(10, 10), dpi=80, facecolor='w', edgecolor='k') After this all I get is a blank 1000 * 1000 image file. My overall code - import networkx as nx import pickle import matplotlib.pyplot as plt print "Reading from pickle." p_file = open('pickles/names') Names = pickle.load(p_file) p_file.close() p_file = open('pickles/distance') Dist = pickle.load(p_file) p_file.close() G = nx.Graph() print "Inserting Nodes." for n in Names: G.add_node(n) print "Inserting Edges." for i in range(601): for j in range(601): G.add_edge(Names[i],Names[j],weight=Dist[i][j]) print "Drawing Graph." nx.draw(G) print "Saving Figure." #plt.figure(num=None, figsize=(10, 10)) plt.savefig('new.png') print "Success!"

  Read the article

• Loading specific icon size into TIcon from stream (Delphi XE)

  - by moodforaday

  My application downloads and displays favicons for specific websites. I followed Bing's solution for detecting image format from stream, but have hit another snag. Assuming an actual icon image, the code goes like this: var icon : TIcon; begin icon := TIcon.Create; try icon.LoadFromStream( faviconStream ); spFavicon.Glyph.Assign( icon ); finally icon.Free; end; end; (spFavicon is TRzGlyphStatus from Raize Components. Its Glyph property is a TBitmap) Now, this works, but sometimes the downloaded icon contains multiple images in different sizes, e.g. 32x32 in addition to the expected 16x16. For some reason the control's Glyph property picks the larger size. How can I load only the 16x16 size into TIcon, or from TIcon into TBitmap? Test favicon: http://www.kpfa.org/favicon.ico On edit: If at all possible, I'd rather avoid saving the icon to a file first.

  Read the article

• Validations for a has_many/belongs_to relationship

  - by Craig Walker

  I have a Recipe model which has_many Ingredients (which in turn belongs_to Recipe). I want Ingredient to be existent dependent on Recipe; an Ingredient should never exist without a Recipe. I'm trying to enforce the presence of a valid Recipe ID in the Ingredient. I've been doing this with a validates :recipe, :presence => true (Rails 3) statement in Ingredient. This works fine if I save the Recipe before adding an Ingredient to it's ingredients collection. However, if I don't have explicit control over the saving (such as when I'm creating a Recipe and its Ingredients from a nested form) then I get an error: Ingredients recipe can't be blank I can get around this simply by dropping the presence validation on Ingredient.recipe. However, I don't particularly like this, as it means I'm working without a safety net. What is the best way to enforce existence-dependence in Rails? Things I'm considering (please comment on the wisdom of each): Adding a not-null constraint on the ingredients.recipe_id database column, and letting the database do the checking for me. A custom validation that somehow checks whether the Ingredient is in an unsaved recipe's ingredient collection (and thus can't have a recipe_id but is still considered valid).

  Read the article

• Custom Django Field is deciding to work as ForiegnKey for no reason

  - by Joe Simpson

  Hi, i'm making a custom field in Django. There's a problem while trying to save it, it's supposed to save values like this 'user 5' and 'status 9' but instead in the database these fields show up as just the number. Here is the code for the field: def find_key(dic, val): return [k for k, v in dic.items() if v == val][0] class ConnectionField(models.TextField): __metaclass__ = models.SubfieldBase serialize = False description = 'Provides a connection for an object like User, Page, Group etc.' def to_python(self, value): if type(value) != unicode: return value value = value.split(" ") if value[0] == "user": return User.objects.get(pk=value[1]) else: from social.models import connections return get_object_or_404(connections[value[0]], pk=value[1]) def get_prep_value(self, value): from social.models import connections print value, "prep" if type(value) == User: return "user %s" % str(value.pk) elif type(value) in connections.values(): o= "%s %s" % (find_key(connections, type(value)), str(value.pk)) print o, "return" return o else: print "CONNECTION ERROR!" raise TypeError("Value is not connectable!") Connection is just a dictionary with the "status" text linked up to the model for a StatusUpdate. I'm saving a model like this which is causing the issue: Relationship.objects.get_or_create(type="feedback",from_user=request.user,to_user=item) Please can someone help, Many Thanks Joe *_*

  Read the article

• Seeding many to many tables with Entity Framework

  - by Doozer1979

  I have a meeting entity and a users entity which have a many to many relationship. I'm using Autopoco to create seed data for the Users and meetings How do i seed the UserMeetings linking table that is created by EntityFramework with seed data? The linking table has two fields in it; User_Id, and Meeting_ID. I'm looping through the list of users that autopoco creates and attaching a random number of meetings Here's what i've got so far. foreach (var user in userList) { var rand = new Random(); var amountOfMeetingsToAdd = rand.Next(1, 300); for (var i = 0; i <= amountOfMeetingsToAdd; i++) { var randomMeeting = rand.Next(1, MeetingRecords); //Error occurs on This line user.Meetings.Add(_meetings[randomMeeting]); } } I got an 'Object reference not set to an instance of an object.' even though the meeting record that i'm trying to attach does exist. For info all this is happening prior to me saving the context to the DB.

  Read the article

• Hashing the state of a complex object in .NET

  - by Jan

  Some background information: I am working on a C#/WPF application, which basically is about creating, editing, saving and loading some data model. The data model contains of a hierarchy of various objects. There is a "root" object of class A, which has a list of objects of class B, which each has a list of objects of class C, etc. Around 30 classes involved in total. Now my problem is that I want to prompt the user with the usual "you have unsaved changes, save?" dialog, if he tries to exit the program. But how do I know if the data in current loaded model is actually changed? There is of course ways to solve this, like e.g. reloading the model from file and compare against the one in memory value by value or make every UI control set a flag indicating the model has been changed. Now instead, I want to create a hash value based on the model state on load and generate a new value when the user tries to exit, and compare those two. Now the question: So inspired of that, I was wondering if there exist some way to generate a hash value from the (value)state of some arbitrary complex object? Preferably in a generic way, e.g. no need to apply attributes to each involved class/field. One idea could be to use some of .NET's serialization functionality (assuming it will work out-of-the-box in this case) and apply a hash function to the content of the resulting file. However, I guess there exist some more suitable approach. Thanks in advance.

  Read the article

< Previous Page | 94 95 96 97 98 99 100 101 102 103 104 105  | Next Page >