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  • MVC + Is validation attributes enough?

    - by ebb
    My ViewModel has validation attributes that ensure that it wont be empty etc. - Is that enough or should I let my the code contracts I have made be in the ActionResult too? Example: // CreateCaseViewModel.cs public class CreateCaseViewModel { [Required] public string Topic { get; set; } [Required] public string Message { get; set; } } // CaseController.cs [AuthWhere(AuthorizeRole.Developer)] [HttpPost] public ActionResult Create(CreateCaseViewModel model) { if(!ModelState.IsValid) { // TODO: some cool stuff? } if (string.IsNullOrWhiteSpace(model.Message)) { throw new ArgumentException("Message cannot be null or empty", model.Message); } if (string.IsNullOrWhiteSpace(model.Topic)) { throw new ArgumentException("Topic cannot be null or empty", model.Topic); } var success = false; string message; var userId = new Guid(_membershipService.GetUserByUserName(User.Identity.Name).ProviderUserKey.ToString()); if(userId == Guid.Empty) { throw new ArgumentException("UserId cannot be empty"); } Case createCase = _caseService.CreateCase(model.Topic, model.Message); if(createCase == null) { throw new ArgumentException("Case cannot be null"); } if(_caseService.AddCase(createCase, userId)) { message = ControllerResources.CaseCreateFail; } else { success = true; message = ControllerResources.CaseCreateSuccess; } return Json(new { Success = success, Message = message, Partial = RenderPartialViewToString(ListView, GetCases) }); }

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  • Python scope problems only when _assigning_ to a variable

    - by wallacoloo
    So I'm having a very strange error right now. I found where it happens, and here's the simplest code that can reproduce it. def parse_ops(str_in): c_type = "operator" def c_dat_check_type(t): print c_type #c_type = t c_dat_check_type("number") >>> parse_ops("12+a*2.5") If you run it as-is, it prints "operator". But if you uncomment that line, it gives an error: Traceback (most recent call last): File "<pyshell#212>", line 1, in <module> parse_ops("12+a*2.5") File "<pyshell#211>", line 7, in parse_ops c_dat_check_type("number") File "<pyshell#211>", line 4, in c_dat_check_type print c_type UnboundLocalError: local variable 'c_type' referenced before assignment Notice the error occurs on the line that worked just fine before. Any ideas what causes this and how I can fix this? I'm using Python 2.6.1.

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  • How can get unique values from data table using dql?

    - by piemesons
    I am having a table in which there is a column in which various values are stored.i want to retrieve unique values from that table using dql. Doctrine_Query::create() ->select('rec.school') ->from('Records rec') ->where("rec.city='$city' ") ->execute(); Now i want only unique values. Can anybody tell me how to do that... Edit Table Structure: CREATE TABLE IF NOT EXISTS `records` ( `id` int(11) NOT NULL AUTO_INCREMENT, `state` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `city` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `school` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=16334 ; This is the Query I am using: Doctrine_Query::create() ->select('DISTINCT rec.city') ->from('Records rec') ->where("rec.state = '$state'") // ->getSql(); ->execute(); Generting Sql for this gives me: SELECT DISTINCT r.id AS r__id, r.city AS r__city FROM records r WHERE r.state = 'AR' Now check the sql generated:::: DISTINCT is on 'id' column where as i want Distinct on city column. Anybody know how to fix this. EDIT2 Id is unique cause its an auto incremental value.Ya i have some real duplicates in city column like: Delhi and Delhi. Right.. Now when i am trying to fetch data from it, I am getting Delhi two times. How can i make query like this: select DISTINCT rec.city where state="xyz"; Cause this will give me the proper output. EDIT3: Anybody who can tell me how to figure out this query..???

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  • Is it necessary to mysql real escape when using alter table?

    - by cgwebprojects
    I noticed the other day that I cannot bind variables when using PDO with ALTER TABLE for example the following example will not work, $q = $dbc -> prepare("ALTER TABLE emblems ADD ? TINYINT(1) UNSIGNED NOT NULL DEFAULT '0', ADD ? DATETIME NOT NULL"); $q -> execute(array($emblemDB, $emblemDB . 'Date')); So is it necessary to use mysql_real_escape string and do it like below, // ESCAPE NAME FOR MYSQL INSERTION $emblemDB = mysql_real_escape_string($emblemDB); // INSERT EMBLEM DETAILS INTO DATABASE $q = $dbc -> prepare("ALTER TABLE emblems ADD " . $emblemDB . " TINYINT(1) UNSIGNED NOT NULL DEFAULT '0', ADD " . $emblemDB . "Date DATETIME NOT NULL"); $q -> execute(); Or do I not need to add in mysql_real_escape_string? As the only thing the query can do is ADD columns? Thanks

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  • distinguishing a string with flex

    - by haluk
    Hi, I need to tokenize some strings which will be splitted of according to operators like = and !=. I was successful using regex until the string has != operator. In my case, string was seperated into two parts, which is expected but ! mark is in the left side even it is part of given operator. Therefore, I believe that regex is not suitable for it and I want to benefit from lex. Since I do not have enough knowledge and experience with lex, I am not sure whether it fits my work or not. Basically, I am trying to do replace the right hand side of the operators with actual values from other data. Do you people think that can it be helpful for my case? Thanks.

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  • How to refactor this duplicated LINQ code?

    - by benrick
    I am trying to figure out how to refactor this LINQ code nicely. This code and other similar code repeats within the same file as well as in other files. Sometime the data being manipulated is identical and sometimes the data changes and the logic remains the same. Here is an example of duplicated logic operating on different fields of different objects. public IEnumerable<FooDataItem> GetDataItemsByColor(IEnumerable<BarDto> dtos) { double totalNumber = dtos.Where(x => x.Color != null).Sum(p => p.Number); return from stat in dtos where stat.Color != null group stat by stat.Color into gr orderby gr.Sum(p => p.Number) descending select new FooDataItem { Color = gr.Key, NumberTotal = gr.Sum(p => p.Number), NumberPercentage = gr.Sum(p => p.Number) / totalNumber }; } public IEnumerable<FooDataItem> GetDataItemsByName(IEnumerable<BarDto> dtos) { double totalData = dtos.Where(x => x.Name != null).Sum(v => v.Data); return from stat in dtos where stat.Name != null group stat by stat.Name into gr orderby gr.Sum(v => v.Data) descending select new FooDataItem { Name = gr.Key, DataTotal = gr.Sum(v => v.Data), DataPercentage = gr.Sum(v => v.Data) / totalData }; } Anyone have a good way of refactoring this?

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  • C++ enumeration

    - by asli
    Hi,my question is about enumeration,my codes are : #include<iostream> using namespace std; int main() { enum bolumler {programcilik,donanim,muhasebe,motor,buro} bolum; bolum = donanim; cout << bolum << endl; bolum += 2; // bolum=motor cout << bolum; return 0; } The output should be 1 3 but according to these codes the error is: error C2676: binary '+=' : 'enum main::bolumler' does not define this operator or a conversion to a type acceptable to the predefined operator Error executing cl.exe. 111.obj - 1 error(s), 0 warning(s) Can you help me ?The other question is what can I do if I want to see the output like that "muhasebe"?

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  • JDBC programms running long time performance issue

    - by phyerbarte
    My program has an issue with Oracle query performance, I believe the SQL have good performance, because it returns quickly in SQLPlus. But when my program has been running for a long time, like 1 week, the SQL query (using JDBC) becomes slower (In my logs, the query time is much longer than when I originally started the program). When I restart my program, the query performance comes back to normal. I think it is could be something wrong with the way I use the preparedStatement, because the SQL I'm using does not use placeholders "?" at all. Just a complex select query. The query process is done by a util class. Here is the pertinent code building the query: public List<String[]> query(String sql, String[] args) { Connection conn = null; conn = openConnection(); conn.setAutocommit(true); .... PreparedStatement preStatm = null; ResultSet rs = null; ....//set preparedstatment arg code rs = preStatm.executeQuery(); .... finally{ //close rs //close prestatm //close connection } } In my case, the args is always null, so it just passes a query sql to this query method. Is that possible this way could slow down the DB query after program long time running? Or I should use statement instead, or just pass args with "?" in the SQL? How can I find out the root cause for my issue? Thanks.

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  • linked list sort function only loops once

    - by Tristan Pearce
    i have a singly linked list that i am trying to sort from least to greatest by price. here is what i have so far struct part { char* name; float price; int quantity; struct part *next; }; typedef struct part partType; partType *sort_price(partType **item) { partType *temp1 = *item; partType *temp2 = (*item)->next; if ( *item == NULL || (*item)->next == NULL ) return *item; else { while ( temp2 != NULL && temp2->next != NULL ){ if (temp2->price > temp2->next->price){ temp1->next = temp2->next; temp2->next = temp2->next->next; temp1->next->next = temp2; } temp1 = temp2; temp2 = temp2->next; } } return *item; } the list is already populated but when i call the sort function it only swaps the first two nodes that satisfy the condition in the if statement. I dont understand why it doesnt do the check again after the two temp pointers are incremented.

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  • help in compare validate in c#

    - by scatman
    i have 2 textboxes that i am filling with StartDate, and Endate. i want to use the compareValidator to make sure that the StartDate is less that the EndDate. i used this: <asp:CompareValidator ID="Comp" ControlToValidate="txtStartDate" ControlToCompare="txtEndDate" Operator="LessThan" Type="Date" runat="server" Display="dynamic" Text="Failed!" /> the validator is always giving me Failed no matter what the dates are. if startdateendate or vise versa, Failed appears. i am using (MM/dd/yyyy) format in the textboxes. EDIT: ok i solved the problem. if anyone interested here is the new comparevalidator: <asp:CompareValidator ID="Comp" ControlToValidate="txtEndDate" ControlToCompare="txtStartDate" Operator="GreaterThan" Type="Date" runat="server" Display="dynamic" Text="Failed!" />

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  • Making two Windows using CreateWindowsEx()

    - by Jamie Keeling
    Hello, I have a windows form that has a simple menu and performs a simple operation, I want to be able to create another windows form with all the functionality of a menu bar, message pump etc.. as a separate thread so I can then share the results of the operation to the second window. I.E. 1) Form A opens Form B opens as a separate thread 2)Form A performs operation 3)Form A passes results via memory to Form B 4)Form B display results I'm confused as to how to go about it, the main app runs fine but i'm not sure how to add a second window if the first one already exists. I think that using CreateWindow will allow me to make another window but again i'm not sure how to access the message pump so I can respond to certain events like WM_CREATE on the second window. I hope it makes sense. Thanks! Edit: I've attempted to make a second window and although this does compile, no windows show atall on build. ////////////////////// // WINDOWS FUNCTION // ////////////////////// LRESULT CALLBACK WindowFunc(HWND hMainWindow, UINT message, WPARAM wParam, LPARAM lParam) { //Fields WCHAR buffer[256]; struct DiceData storage; HWND hwnd; // Act on current message switch(message) { case WM_CREATE: AddMenus(hMainWindow); hwnd = CreateWindowEx( 0, "ChildWClass", (LPCTSTR) NULL, WS_CHILD | WS_BORDER | WS_VISIBLE, 0, 0, 0, 0, hMainWindow, NULL, NULL, NULL); ShowWindow(hwnd, SW_SHOW); break; Any suggestions as to why this happens?

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  • Query about running a program through valgrind and getting false results comparing to other systems.

    - by FILIaS
    Yesterday i posted this: What's the problem with this code? [hashtable in C] and paxdiablo offered to help me. He posted a sample of code and asked me to run it through valgrind on my machine. This code normally generates: 12,4 But on my machine, i get 24,8. The doubled! I'm just curious why is that happening. Hope sb has a good explaination. I post also paxdiablo's code (for anyone who cant find it.) #include <stdio.h> #include <stdlib.h> typedef struct HashTable { int size ; struct List *head; struct List *tail; } HashTable; typedef struct List { char *number; char *name; int time; struct List *next; } List; #define size_of_table 211 HashTable *createHashTable(void) { HashTable *new_table = malloc(sizeof(*new_table)*size_of_table); //line 606 printf ("%d\n", sizeof(*new_table)); printf ("%d\n", sizeof(new_table)); if (new_table == NULL) { return NULL; } int i=0; for(i; i<size_of_table; i++) { new_table[i].size=0; new_table[i].head=NULL; new_table[i].tail=NULL; } return new_table; } int main(void) { HashTable *x = createHashTable(); free (x); return 0; }

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  • Django forms I cannot save picture file

    - by dana
    i have the model: class OpenCv(models.Model): created_by = models.ForeignKey(User, blank=True) first_name = models.CharField(('first name'), max_length=30, blank=True) last_name = models.CharField(('last name'), max_length=30, blank=True) url = models.URLField(verify_exists=True) picture = models.ImageField(help_text=('Upload an image (max %s kilobytes)' %settings.MAX_PHOTO_UPLOAD_SIZE),upload_to='jakido/avatar',blank=True, null= True) bio = models.CharField(('bio'), max_length=180, blank=True) date_birth = models.DateField(blank=True,null=True) domain = models.CharField(('domain'), max_length=30, blank=True, choices = domain_choices) specialisation = models.CharField(('specialization'), max_length=30, blank=True) degree = models.CharField(('degree'), max_length=30, choices = degree_choices) year_last_degree = models.CharField(('year last degree'), max_length=30, blank=True,choices = year_last_degree_choices) lyceum = models.CharField(('lyceum'), max_length=30, blank=True) faculty = models.ForeignKey(Faculty, blank=True,null=True) references = models.CharField(('references'), max_length=30, blank=True) workplace = models.ForeignKey(Workplace, blank=True,null=True) objects = OpenCvManager() the form: class OpencvForm(ModelForm): class Meta: model = OpenCv fields = ['first_name','last_name','url','picture','bio','domain','specialisation','degree','year_last_degree','lyceum','references'] and the view: def save_opencv(request): if request.method == 'POST': form = OpencvForm(request.POST, request.FILES) # if 'picture' in request.FILES: file = request.FILES['picture'] filename = file['filename'] fd = open('%s/%s' % (MEDIA_ROOT, filename), 'wb') fd.write(file['content']) fd.close() if form.is_valid(): new_obj = form.save(commit=False) new_obj.picture = form.cleaned_data['picture'] new_obj.created_by = request.user new_obj.save() return HttpResponseRedirect('.') else: form = OpencvForm() return render_to_response('opencv/opencv_form.html', { 'form': form, }, context_instance=RequestContext(request)) but i don't seem to save the picture in my database... something is wrong, and i can't figure out what :(

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  • Android - BitmapFactory.decodeByteArray - OutOfMemoryError (OOM)

    - by Bob Keathley
    I have read 100s of article about the OOM problem. Most are in regard to large bitmaps. I am doing a mapping application where we download 256x256 weather overlay tiles. Most are totally transparent and very small. I just got a crash on a bitmap stream that was 442 Bytes long while calling BitmapFactory.decodeByteArray(....). The Exception states: java.lang.OutOfMemoryError: bitmap size exceeds VM budget(Heap Size=9415KB, Allocated=5192KB, Bitmap Size=23671KB) The code is: protected Bitmap retrieveImageData() throws IOException { URL url = new URL(imageUrl); InputStream in = null; OutputStream out = null; HttpURLConnection connection = (HttpURLConnection) url.openConnection(); // determine the image size and allocate a buffer int fileSize = connection.getContentLength(); if (fileSize < 0) { return null; } byte[] imageData = new byte[fileSize]; // download the file //Log.d(LOG_TAG, "fetching image " + imageUrl + " (" + fileSize + ")"); BufferedInputStream istream = new BufferedInputStream(connection.getInputStream()); int bytesRead = 0; int offset = 0; while (bytesRead != -1 && offset < fileSize) { bytesRead = istream.read(imageData, offset, fileSize - offset); offset += bytesRead; } // clean up istream.close(); connection.disconnect(); Bitmap bitmap = null; try { bitmap = BitmapFactory.decodeByteArray(imageData, 0, bytesRead); } catch (OutOfMemoryError e) { Log.e("Map", "Tile Loader (241) Out Of Memory Error " + e.getLocalizedMessage()); System.gc(); } return bitmap; } Here is what I see in the debugger: bytesRead = 442 So the Bitmap data is 442 Bytes. Why would it be trying to create a 23671KB Bitmap and running out of memory?

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  • Entity Framework does not map 2 columns from a SqlQuery calling a stored procedure

    - by user1783530
    I'm using Code First and am trying to call a stored procedure and have it map to one of my classes. I created a stored procedure, BOMComponentChild, that returns details of a Component with information of its hierarchy in PartsPath and MyPath. I have a class for the output of this stored procedure. I'm having an issue where everything except the two columns, PartsPath and MyPath, are being mapped correctly with these two properties ending up as Nothing. I searched around and from my understanding the mapping bypasses any Entity Framework name mapping and uses column name to property name. The names are the same and I'm not sure why it is only these two columns. The last part of the stored procedure is: SELECT t.ParentID ,t.ComponentID ,c.PartNumber ,t.PartsPath ,t.MyPath ,t.Layer ,c.[Description] ,loc.LocationID ,loc.LocationName ,CASE WHEN sup.SupplierID IS NULL THEN 1 ELSE sup.SupplierID END AS SupplierID ,CASE WHEN sup.SupplierName IS NULL THEN 'Scinomix' ELSE sup.SupplierName END AS SupplierName ,c.Active ,c.QA ,c.IsAssembly ,c.IsPurchasable ,c.IsMachined ,t.QtyRequired ,t.TotalQty FROM BuildProducts t INNER JOIN [dbo].[BOMComponent] c ON c.ComponentID = t.ComponentID LEFT JOIN [dbo].[BOMSupplier] bsup ON bsup.ComponentID = t.ComponentID AND bsup.IsDefault = 1 LEFT JOIN [dbo].[LookupSupplier] sup ON sup.SupplierID = bsup.SupplierID LEFT JOIN [dbo].[LookupLocation] loc ON loc.LocationID = c.LocationID WHERE (@IsAssembly IS NULL OR IsAssembly = @IsAssembly) ORDER BY t.MyPath and the class it maps to is: Public Class BOMComponentChild Public Property ParentID As Nullable(Of Integer) Public Property ComponentID As Integer Public Property PartNumber As String Public Property MyPath As String Public Property PartsPath As String Public Property Layer As Integer Public Property Description As String Public Property LocationID As Integer Public Property LocationName As String Public Property SupplierID As Integer Public Property SupplierName As String Public Property Active As Boolean Public Property QA As Boolean Public Property IsAssembly As Boolean Public Property IsPurchasable As Boolean Public Property IsMachined As Boolean Public Property QtyRequired As Integer Public Property TotalQty As Integer Public Property Children As IDictionary(Of String, BOMComponentChild) = New Dictionary(Of String, BOMComponentChild) End Class I am trying to call it like this: Me.Database.SqlQuery(Of BOMComponentChild)("EXEC [BOMComponentChild] @ComponentID, @PathPrefix, @IsAssembly", params).ToList() When I run the stored procedure in management studio, the columns are correct and not null. I just can't figure out why these won't map as they are the important information in the stored procedure. The types for PartsPath and MyPath are varchar(50).

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  • BASH: Checking for environment variables

    - by Hamza
    Hi folks, I am trying to check the value of an environment variable and depending on the value do certain things and it works fine as long as the variable is set. When it isn't though I get a whole bunch of errors (as BASH is trying to compare the string I specify with an undefined variable, I guess) I tried implementing an extra check to prevent it happening but no luck. The block of code I am using is: #!/bin/bash if [ -n $TESTVAR ] then if [ $TESTVAR == "x" ] then echo "foo" exit elif [ $TESTVAR == "y" ] then echo "bar" exit else echo "baz" exit fi else echo -e "TESTVAR not set\n" fi And this the output: $ export TESTVAR=x $ ./testenv.sh foo $ export TESTVAR=y $ ./testenv.sh bar $ export TESTVAR=q $ ./testenv.sh baz $ unset TESTVAR $ ./testenv.sh ./testenv.sh: line 5: [: ==: unary operator expected ./testenv.sh: line 9: [: ==: unary operator expected baz My question is, shouldn't 'unset TESTVAR' nullify it? It doesn't seem to be the case... Thanks.

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  • Selectively search and replace certain lines using a regular expression

    - by eneveu
    I have a file containing a lot of SQL statements, such as: CREATE TABLE "USER" ( "ID" INTEGER PRIMARY KEY, "NAME" CHARACTER VARYING(50) NOT NULL, "AGE" INTEGER NOT NULL ); COPY "USER" (id, name, age) FROM stdin; 1 Skywalker 19 2 Kenobi 57 I want the column names in the COPY statements to be uppercased and quoted: COPY "USER" ("ID", "NAME", "AGE") FROM stdin; Using sed, I found the following regexp: sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' It does replace the column names, but it is not selective enough, and replaces other words in the file: ~/test]$sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' star_wars_example CREATE TABLE "USER" ( "ID" INTEGER PRIMARY "KEY", "NAME" CHARACTER VARYING("50")NOT "NULL", "AGE" INTEGER NOT NULL ); COPY "USER" ("ID", "NAME", "AGE") FROM stdin; 1 Skywalker 19 2 Kenobi 57 To avoid this problem, I want sed to only apply my regexp to the lines starting with COPY and ending with FROM stdin;. I have looked into lookahead / lookbehind, but they are not supported in sed. They seem to be supported in super-sed, but I am currently using Cygwin (Windows is mandatory here...) and it does not seem available in the package list. Is there a way to force sed to only consider specific line? I've considered piping my file through grep before applying sed, but other lines will then disappear from the output. Am I missing something obvious? It would be great if the answer was easily applicable on a default Cygwin install. I guess I could try installing super-sed on cygwin, but I'd like to know if there are more obvious ideas

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  • Javascript Object Properties go to undefined after ajax request returns

    - by adasdas
    if you have an object and set a property for it, you can access that property in a function called on that object. but if you call a function and do an ajax request such that a different function is called from onreadystatechange, that secondary response function does not have access to the property. Thats a little confusing so see what I mean here. The property this.name is the one that changes. //from W3Schools website function getXHR(){if (window.XMLHttpRequest){return new XMLHttpRequest();}if (window.ActiveXObject){return new ActiveXObject("Microsoft.XMLHTTP");}return null;} function TestObject() { this.name = ""; //public var xhr = null; //private var response = function() //private { if(xhr.readyState > 3) { alert("B: my name is " + this.name); } } this.send = function() //public { alert("A: my name is " + this.name); if(xhr === null) { xhr = getXHR(); } var url = "http://google.com"; xhr.onreadystatechange = response; xhr.open("GET", url, true); xhr.send(null); } } var o = new TestObject(); o.name = "Ice Cube"; o.send(); Results are: A: my name is IceCube B: my name is undefined If response is public this happens as well. If xhr is public this also happens. Something occurs so that the response function called doesnt have access to the same parameters.

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  • Is there an efficient way in LINQ to use a contains match if and only if there is no exact match?

    - by Peter
    I have an application where I am taking a large number of 'product names' input by a user and retrieving some information about each product. The problem is, the user may input a partial name or even a wrong name, so I want to return the closest matches for further selection. Essentially if product name A exactly matches a record, return that, otherwise return any contains matches. Otherwise return null. I have done this with three separate statements, and I was wondering if there was a more efficient way to do this. I am using LINQ to EF, but I materialize the products to a list first for performance reasons. productNames is a List of product names (input by the user). products is a List of product 'records' var directMatches = (from s in productNames join p in products on s.ToLower() equals p.name.ToLower() into result from r in result.DefaultIfEmpty() select new {Key = s, Product = r}); var containsMatches = (from d in directMatches from p in products where d.Product == null && p.name.ToLower().Contains(d.Key) select new { d.Key, Product = p }); var matches = from d in directMatches join c in containsMatches on d.Key equals c.Key into result from r in result.DefaultIfEmpty() select new {d.Key, Product = d.Product ?? (r != null ? r.Product: null) };

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  • How to handle window closed in the middle of a long running operation gracefully?

    - by Marek
    We have the following method called directly from the UI thread: void DoLengthyProcessing() { DoStuff(); var items = DoMoreStuff(); //do even more stuff - 200 lines of code trimmed this.someControl.PrepareForBigThing(); //someControl is a big user control //additional 100 lines of code that access this.someControl this.someControl.Finish(items); } Many of the called methods call Application.DoEvents() (and they do so many times) (do not ask me why, this is black magic written by black magic programmers and it can not be changed because everyone is scared what the impact would be) and there is also an operation running on a background thread involved in the processing. As a result, the window is not fully nonresponsive and can be closed manually during the processing. The Dispose method of the form "releases" the someControl variable by setting it to null. As a result, in case the user closes the window during the lengthy process, a null reference exception is thrown. How to handle this gracefully without just catching and logging the exception caused by disposal? Assigning the someControl instance to a temporary variable in the beginning of the method - but the control contains many subcontrols with similar disposal scheme - sets them to null and this causes null reference exceptions in other place put if (this.IsDisposed) return; calls before every access of the someControl variable. - making the already nasty long method even longer and unreadable. in Closing event, just indicate that we should close and only hide the window. Dispose it at the end of the lengthy operation. This is not very viable because there are many other methods involved (think 20K LOC for a single control) that would need to handle this mechanism as well. How to most effectively handle window disposal (by user action) in the middle of this kind of processing?

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  • C# Convert string to nullable type (int, double, etc...)

    - by Nathan Koop
    I am attempting to do some data conversion. Unfortunately, much of the data is in strings, where it should be int's or double, etc... So what I've got is something like: double? amount = Convert.ToDouble(strAmount); The problem with this approach is if strAmount is empty, if it's empty I want it to amount to be null, so when I add it into the database the column will be null. So I ended up writing this: double? amount = null; if(strAmount.Trim().Length>0) { amount = Convert.ToDouble(strAmount); } Now this works fine, but I now have five lines of code instead of one. This makes things a little more difficult to read, especially when I have a large amount of columns to convert. I thought I'd use an extension to the string class and generic's to pass in the type, this is because it could be a double, or an int, or a long. So I tried this: public static class GenericExtension { public static Nullable<T> ConvertToNullable<T>(this string s, T type) where T: struct { if (s.Trim().Length > 0) { return (Nullable<T>)s; } return null; } } But I get the error: Cannot convert type 'string' to 'T?' Is there a way around this? I am not very familiar with creating methods using generics.

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  • C# Type Casting at Runtimefor Array.SetValue

    - by sprocketonline
    I'm trying to create an array using reflection, and insert values into it. I'm trying to do this for many different types so would like a createAndFillArray function capable of this : Type t1 = typeof(A); Type t2 = typeof(B); double exampleA = 22.5; int exampleB = 43; Array arrA = createAndFillArray(t1, exampleA); Array arrB = createAndFillArray(t2, exampleB); private Array createAndFillArray(Type t, object val){ Array arr = Array.CreateInstance( t, 1); //length 1 in this example only, real-world is of variable length. arr.SetValue( val, 0 ); //this causes the following error: "System.InvalidCastException : Object cannot be stored in an array of this type." return arr; } with the class A being as follows: public class A{ public A(){} private double val; public double Value{ get{ return val; } set{ this.val = value; } } public static implicit operator A(double d){ A a = new A(); a.Value = d; return a; } } and class B being very similar, but with int: public class B{ public B(){} private double val; public double Value{ get{ return val; } set{ this.val = value; } } public static implicit operator B(double d){ B b = new B(); b.Value = d; return b; } } I hoped that the implicit operator would have ensured that the double be converted to class A, or the int to class B, and the error avoided; but this is obviously not so. The above is used in a custom deserialization class, which takes data from a custom data format and fills in the corresponding .Net object properties. I'm doing this via reflection and at runtime, so I think both are unavoidable. I'm targeting the C# 2.0 framework. I've dozens, if not hundreds, of classes similar to A and B, so would prefer to find a solution which improved on the createAndFillArray method rather than a solution which altered these classes.

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  • Flex + PHP + ValueObjects

    - by Tempname
    I have a php/flex value object that I am using to transmit data to/from in my application. Everything works great php-flex, but I am having an issue with flex-php. In my MergeTemplateService.php service I have the following code. This is the method that flex hits directly: function updateTemplate($valueObject){ $object = DAOFactory::getMergeTemplateDAO()->update($valueObject); return $object; } I am passing a value object that from flex looks like this: (com.rottmanj.vo::MergeTemplateVO)#0 communityID = 0 creationDate = (null) enterpriseID = 0 lastModifyDate = (null) templateID = 2 templateName = "My New Test Template" userID = 0 The issue I am having is that my updateTemplate method sees the value object as an array and not an object. In my amfphp globals.php I have set my voPath as: $voPath = "services/class/dto/"; Any help with this is greatly appreciated Here are my two value objects: AS3 VO: package com.rottmanj.vo { [RemoteClass(alias="MergeTemplate")] public class MergeTemplateVO { public var templateID:int; public var templateName:String; public var communityID:int; public var enterpriseID:int; public var userID:int; public var creationDate:String; public var lastModifyDate:String public function MergeTemplateVO(data:Object = null):void { if(data != null) { templateID = data.templateID; templateName = data.templateName; communityID = data.communityID; enterpriseID = data.enterpriseID; userID = data.userID; creationDate = data.creationDate; lastModifyDate = data.lastModifyDate; } } } } PHPVO: <?php class MergeTemplate{ var $templateID; var $templateName; var $communityID; var $enterpriseID; var $userID; var $creationDate; var $lastModifyDate; var $_explictType = 'MergeTemplate'; } ?>

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  • Why are there two implementations of std::sort (with and without a comparator) rather than one implementation with a default template parameter?

    - by PolyVox
    In my code I'm adopting a design strategy which is similar to some standard library algorithms in that the exact behavior can be customized by a function object. The simplest example is std::sort, where a function object can control how the comparison is made between objects. I notice that the Visual C++ provides two implementations of std::sort, which naturally involves code duplication. I would have imagined that it was instead possible to have only one implementation, and provide a default comparator (using operator< ) as a default template parameter. What is the rational behind two separate versions? Would my suggestion make the interface more complex in some way? Or result in confusing error messages when the object does not provide operator Thanks, David

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