Search Results

Search found 12898 results on 516 pages for 'expression engine'.

Page 448/516 | < Previous Page | 444 445 446 447 448 449 450 451 452 453 454 455  | Next Page >

• ViewModel Views relation/link/syncroniztion

  - by mehran

  Third try to describing problem: Try 1: Sunchronizing view model and view Try2: WPF ViewModel not active presenter Try3: I have some class for view models: public class Node : INotifyPropertyChanged { Guid NodeId { get; set; } public string Name { get; set; } } public class Connection: INotifyPropertyChanged { public Node StartNode { get; set; } public Node EndNode { get; set; } } public class SettingsPackModel { public List<Node> Nodes { get; private set; } public List<Connection> Connections { get; private set; } } I also have some templates to displays these models: <DataTemplate DataType="{x:Type vm:Node}">…</DataTemplate> <DataTemplate DataType="{x:Type vm:Connection}"> <my:ConnectionElment StartNodeElment="???" EndNodeElment="???"> </my:ConnectionElment> <DataTemplate> But the problem is that DataTemplate for Connection need reference ot two element of type UIElement , how can I pass these two, how can I fill ??? in above expression?

  Read the article

• How to safely transfer reference to object across window?

  - by Morgan Cheng

  I'm debugging a web application. Javasript in one window create one object and use it as argument to invoke global method in another window. Pseudo code is like below. var obj = new Foo(); anotherWin.bar(obj); In anotherWin, the argument is stored in global variable. var g_obj; function bar(obj) { g_obj = obj; ... } When other function tries to reference g_obj.Id, it throws exception "Cannot evaluate expression". This happens in IE8.0.7600.16385 on Windows 7. In Visual Studio debugger, when this exception happens, the g_obj shows as {...} It looks all its properties are lost. Perhaps the root reason is the object is created in one window but only referenced in another window. The object might be garbage-collected at any time. Is there any way to work around this?

  Read the article

• Bind button visibility to the expresion (C#)

  - by drasto

  I have a delete button in each row of GridView (component ASP.NET). I want some of the delete buttons to be invisible. The visibility of the delete button should depend on the data that are back the row. GridView is backed by EntityDataSource. GridView displays entities called Category, one instance in each row. Entity Category has (besides others) also a field of type EntityCollection. Name of that field is Items. Basically I want to allow user to delete a row only if the Items field of backing Category entity is an empty collection. I cannot make up the binding of Visible property. I have no experience with bindings and Google does not really help. This is how the button looks right now: <asp:Button ID="DeleteButton" runat="server" CommandName="Delete" Text="Delete" Visible=??? ></asp:Button> I don't know what should replace ???. The button schold be visible only when this expression evaluates to true: ((SimpleEShop.Model.Category) dataItem).Items.LongCount() <= 0 where dataItem variable contains data of current row in the table. What is the binding that I need ?

  Read the article

• PHP Regex to match lines with all-caps with occaisional hyphens.

  - by Yaaqov

  I'm trying to to convert an existing PHP Regular Expression match case to apply to a slightly different style of document. Here's the original style of the document: **FOODS - TYPE A** ___________________________________ **PRODUCT** 1) Mi Pueblito Queso Fresco Authentic Mexican Style Fresh Cheese; 2) La Fe String Cheese **CODE** Sell by date going back to February 1, 2009 And the successfully-running PHP Regex match code that only returns "true" if the line is surrounded by asterisks, and stores each side of the "-" as $m[1] and $m[2], respectively. if ( preg_match('#^\*\*([^-]+)(?:-(.*))?\*\*$#', $line, $m) ) { // only for **header - subheader** $m[2] is set. if ( isset($m[2]) ) { return array(TYPE_HEADER, array(trim($m[1]), trim($m[2]))); } else { return array(TYPE_KEY, array($m[1])); } } So, for line 1: $m[1] = "FOODS" AND $m[2] = "TYPE A"; Line 2 would be skipped; Line 3: $m[1] = "PRODUCT", etc. The question: How would I re-write the above regex match if the headers did not have the asterisks, but still was all-caps, and was at least 4 characters long? For example: FOODS - TYPE A ___________________________________ PRODUCT 1) Mi Pueblito Queso Fresco Authentic Mexican Style Fresh Cheese; 2) La Fe String Cheese CODE Sell by date going back to February 1, 2009 Thank you.

  Read the article

• How to define a "complicated" ComputedColumn in SQL Server?

  - by Slauma

  SQL Server Beginner question: I'm trying to introduce a computed column in SQL Server (2008). In the table designer of SQL Server Management Studio I can do this, but the designer only offers me one single edit cell to define the expression for this column. Since my computed column will be rather complicated (depending on several database fields and with some case differentiations) I'd like to have a more comfortable and maintainable way to enter the column definition (including line breaks for formatting and so on). I've seen there is an option to define functions in SQL Server (scalar value or table value functions). Is it perhaps better to define such a function and use this function as the column specification? And what kind of function (scalar value, table value)? To make a simplified example: I have two database columns: DateTime1 (smalldatetime, NULL) DateTime2 (smalldatetime, NULL) Now I want to define a computed column "Status" which can have four possible values. In Dummy language: if (DateTime1 IS NULL and DateTime2 IS NULL) set Status = 0 else if (DateTime1 IS NULL and DateTime2 IS NOT NULL) set Status = 1 else if (DateTime1 IS NOT NULL and DateTime2 IS NULL) set Status = 2 else set Status = 3 Ideally I would like to have a function GetStatus() which can access the different column values of the table row which I want to compute the value of "Status" for, and then only define the computed column specification as GetStatus() without parameters. Is that possible at all? Or what is the best way to work with "complicated" computed column definitions? Thank you for tips in advance!

  Read the article

• Enums, Constructor overloads with similar conversions.

  - by David Thornley

  Why does VisualC++ (2008) get confused 'C2666: 2 overloads have similar conversions' when I specify an enum as the second parameter, but not when I define a bool type? Shouldn't type matching already rule out the second constructor because it is of a 'basic_string' type? #include <string> using namespace std; enum EMyEnum { mbOne, mbTwo }; class test { public: #if 1 // 0 = COMPILE_OK, 1 = COMPILE_FAIL test(basic_string<char> myString, EMyEnum myBool2) { } test(bool myBool, bool myBool2) { } #else test(basic_string<char> myString, bool myBool2) { } test(bool myBool, bool myBool2) { } #endif }; void testme() { test("test", mbOne); } I can work around this by specifying a reference 'ie. basic_string &myString' but not if it is 'const basic_string &myString'. Also calling explicitly via "test((basic_string)"test", mbOne);" also works. I suspect this has something to do with every expression/type being resolved to a bool via an inherent '!=0'. Curious for comments all the same :)

  Read the article

• Silverlight 3 data-binding child property doesn't update

  - by sonofpirate

  I have a Silverlight control that has my root ViewModel object as it's data source. The ViewModel exposes a list of Cards as well as a SelectedCard property which is bound to a drop-down list at the top of the view. I then have a form of sorts at the bottom that displays the properties of the SelectedCard. My XAML appears as (reduced for simplicity): <StackPanel Orientation="Vertical"> <ComboBox DisplayMemberPath="Name" ItemsSource="{Binding Path=Cards}" SelectedItem="{Binding Path=SelectedCard, Mode=TwoWay}" /> <TextBlock Text="{Binding Path=SelectedCard.Name}" /> <ListBox DisplayMemberPath="Name" ItemsSource="{Binding Path=SelectedCard.PendingTransactions}" /> </StackPanel> I would expect the TextBlock and ListBox to update whenever I select a new item in the ComboBox, but this is not the case. I'm sure it has to do with the fact that the TextBlock and ListBox are actually bound to properties of the SelectedCard so it is listening for property change notifications for the properties on that object. But, I would have thought that data-binding would be smart enough to recognize that the parent object in the binding expression had changed and update the entire binding. It bears noting that the PendingTransactions property (bound to the ListBox) is lazy-loaded. So, the first time I select an item in the ComboBox, I do make the async call and load the list and the UI updates to display the information corresponding to the selected item. However, when I reselect an item, the UI doesn't change! For example, if my original list contains three cards, I select the first card by default. Data-binding does attempt to access the PendingTransactions property on that Card object and updates the ListBox correctly. If I select the second card in the list, the same thing happens and I get the list of PendingTransactions for that card displayed. But, if I select the first card again, nothing changes in my UI! Setting a breakpoint, I am able to confirm that the SelectedCard property is being updated correctly. How can I make this work???

  Read the article

• Type result with Ternary operator in C#

  - by Vaccano

  I am trying to use the ternary operator, but I am getting hung up on the type it thinks the result should be. Below is an example that I have contrived to show the issue I am having: class Program { public static void OutputDateTime(DateTime? datetime) { Console.WriteLine(datetime); } public static bool IsDateTimeHappy(DateTime datetime) { if (DateTime.Compare(datetime, DateTime.Parse("1/1")) == 0) return true; return false; } static void Main(string[] args) { DateTime myDateTime = DateTime.Now; OutputDateTime(IsDateTimeHappy(myDateTime) ? null : myDateTime); Console.ReadLine(); ^ } | } | // This line has the compile issue ---------------+ On the line indicated above, I get the following compile error: Type of conditional expression cannot be determined because there is no implicit conversion between '< null ' and 'System.DateTime' I am confused because the parameter is a nullable type (DateTime?). Why does it need to convert at all? If it is null then use that, if it is a date time then use that. I was under the impression that: condition ? first_expression : second_expression; was the same as: if (condition) first_expression; else second_expression; Clearly this is not the case. What is the reasoning behind this? (NOTE: I know that if I make "myDateTime" a nullable DateTime then it will work. But why does it need it? As I stated earlier this is a contrived example. In my real example "myDateTime" is a data mapped value that cannot be made nullable.)

  Read the article

• How do I get rid of these warnings?

  - by Brian Postow

  This is really several questions, but anyway... I'm working with a big project in XCode, relatively recently ported from MetroWorks (Yes, really) and there's a bunch of warnings that I want to get rid of. Every so often an IMPORTANT warning comes up, but I never look at them because there's too many garbage ones. So, if I can either figure out how to get XCode to stop giving the warning, or actually fix the problem, that would be great. Here are the warnings: It claims that <map.h> is antiquated. However, when I replace it with <map> my files don't compile. Evidently, there's something in map.h that isn't in map... this decimal constant is unsigned only in ISO C90 This is a large number being compared to an unsigned long. I have even cast it, with no effect. enumeral mismatch in conditional expression: <anonymous enum> vs <anonymous enum> This appears to be from a ?: operator. Possibly that the then and else branches don't evaluate to the same type? Except that in at least one case, it's (matchVp == NULL ? noErr : dupFNErr) And since those are both of type OSErr, which is mac defined... I'm not sure what's up. It also seems to come up when I have other pairs of mac constants... multi-character character constant This one is obvious. The problem is that I actually NEED multi-character constants... -fwritable-strings not compatible with literal CF/NSString I unchecked the "Strings are Read-Only" box in both the project and target settings... and it seems to have had no effect...

  Read the article

• A weird crash...

  - by Nima

  Hi, I have a piece of code that runs in debug mode in VS2008, C++. The problem is that when I am debugging the code line by line, at a very weird point of the code, it crashes and says: debug assertion faild. Expression: _BLOCK_TYPE_IS_VALID(pHead-nBlockUse) The crash point is on the first closed curly bracket (after mesh-edges[e].needsUpdate=false;) I don't understand why on a curly bracket? does that make sense to you guys? Can anybody help me understanding what is going on..? for(int e=0; e<mesh->edges.size(); e++) { if(mesh->edges[e].valid && mesh->edges[e].v[0]>=0 && mesh->edges[e].v[1]>=0 && mesh->points[mesh->edges[e].v[0]].writable && mesh->points[mesh->edges[e].v[1]].writable) { //update v_hat and its corresponding error DecEdge Current = DecEdge(e); pair<Point, float> ppf = computeVhat(e); Current.v_hat = ppf.first; Current.error = ppf.second; edgeSoup.push(Current); mesh->edges[e].needsUpdate=false; } }

  Read the article

• Operation is not valid due to the current state of the object?

  - by Bill

  I am programming in C#; the code was working about a week ago, however it throws an exception and I don't understand at all what could be wrong with it. Var root = new CalculationNode(); -> Throw exception. In the call stack thats the only thing listed, I've been told that it could be that I need a clean build, but I am open to any ideas or suggestions. Thanks, -Bill Update: Exception's Detail System.InvalidOperationException was unhandled by user code Message=Operation is not valid due to the current state of the object. Source=Calculator.Logic StackTrace: at ~.Calculator.Logic.MyBaseExpressionParser.Parse(String expression) in ~\Source\Calculator.Logic\MyBaseExpressionParser.cs:line 44 at ~.Calculator.Logic.Tests.MyBaseCalculatorServiceTests.BasicMathDivision() in ~\Projects\Tests\Calculator.Logic.Tests\MyBaseCalculatorServiceTests.cs:line 60 InnerException: CalculationNode's code: public sealed calss CalculationNode { public CalculationNode() { this.Left = null; this.Right = null; this.Element = new CalculationElement(); } public CalculationNode Left {get;set;} public CalculationNode Right {get;set;} public CalculationElement Element {get; set;} } CalculationElement's code: public sealed class CalculationElement { public CalculationElement() { Value = string.Empty; IsOperator = false; } public string Value {get; set} public bool IsOperator {get; set} }

  Read the article

• Can't use Visual Studio 2008 Designer with MVVMLight V3 SP1

  - by mcauthorn

  I wish I knew what I did to cause this, but I cannot use the Visual Studio 2008 Designer at all with with MVVMLight templates. I receive a "Could not create an instance of type 'ViewModelLocator'. in any of my xaml pages. The application builds and runs fine but only the designer is broken. In the App.xaml is <Application x:Class="ExcelReportGenerator.App" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:vm="clr-namespace:ExcelReportGenerator.ViewModel" xmlns:res="clr-namespace:ExcelReportGenerator.Resources" Startup="Application_Startup" mc:Ignorable="d"> <Application.Resources> <!--Global View Model Locator--> <vm:ViewModelLocator x:Key="Locator" d:IsDataSource="True" /> </Application.Resources> I even receive the error when I create a brand new MVVMLight application. The interesting thing is if I use an express version of VS2010 I can view, edit and work in designer just fine. As much as I would love to go to VS2010, I can't right now convince IT to make that move.

  Read the article

• C# Attribute XmlIgnore and XamlWriter class - XmlIgnore not working

  - by Horst Walter

  I have a class, containing a property Brush MyBrush marked as [XmlIgnore]. Nevertheless it is serialized in the stream causing trouble when trying to read via XamlReader. I did some tests, e.g. when changing the visibility (to internal) of the Property it is gone in the stream. Unfortunately I cannot do this in my particular scenario. Did anybody have the same issue and? Do you see any way to work around this? Remark: C# 4.0 as far I can tell This is a method from my Unit Test where I do test the XamlSerialization: // buffer to a StringBuilder StringBuilder sb = new StringBuilder(); XmlWriter writer = XmlWriter.Create(sb, settings); XamlDesignerSerializationManager manager = new XamlDesignerSerializationManager(writer) {XamlWriterMode = XamlWriterMode.Expression}; XamlWriter.Save(testObject, manager); xml = sb.ToString(); Assert.IsTrue(!String.IsNullOrEmpty(xml) && !String.IsNullOrEmpty(xml), "Xaml Serialization failed for " + testObject.GetType() + " no xml string available"); xml = sb.ToString(); MemoryStream ms = xml.StringToStream(); object root = XamlReader.Load(ms); Assert.IsTrue(root != null, "After reading from MemoryStream no result for Xaml Serialization"); In one of my classes I use the Property Brush. In the above code this Unit Tests fails because of a Brush object not serializable is the value. When I remove the Setter (as below, the Unit Test passes. Using the XmlWriter (basically same test as above) it works. In the StringBuffer sb I can see that Property Brush is serialized when the Setter is there and not when removed (most likely another check ignoring the Property because of no setter). Other Properties with [XmlIgnore] are ignored as intended. [XmlIgnore] public Brush MyBrush { get { ..... } // removed because of problem with Serialization // set { ... } }

  Read the article

• Having trouble creating vectors of System::String^

  - by Justen

  So I have a regex expression to parse certain parts of a file name. I'm trying to store each part in its own vector until I use it later, but it won't let me. One error I get when I try making a vector of System::String^ is that error C3698: 'System::String ^' : cannot use this type as argument of 'new' Then, when I try just making a vector of std::string, it can't implicitly convert to type System::String^, and casting won't work either. void parseData() { System::String^ pattern = "(\\D+)(\\d+)(\\w{1})(\\d+)\\.(\\D{3})"; std::vector < System::String^ > x, y, filename, separator; Regex re( pattern ); for ( int i = 0; i < openFileDialog1->FileNames->Length; i++ ) { Match^ m = re.Match( openFileDialog1->FileNames[i] ); filename.push_back( m->Groups[0]->Value );/* x.push_back( m->Groups[1]->Value ); separator.push_back( m->Groups[2]->Value ); y.push_back( m->Groups[3]->Value );*/ } }

  Read the article

• Weird splitter behaviour when moving it

  - by tomo

  My demo app displays two rectangles which should fill whole browser's screen. There is a vertical splitter between them. This looks like a basic scenario but I have no idea how to implement this in xaml. I cannot force this to fill whole screen and when moving splitter then whole screen grows. Can anybody help? <UserControl xmlns:controls="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls" x:Class="SilverlightApplication1.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignWidth="640" d:DesignHeight="480"> <Grid x:Name="LayoutRoot" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto"/> <ColumnDefinition Width="Auto"/> <ColumnDefinition Width="Auto"/> </Grid.ColumnDefinitions> <Border BorderBrush="Black" BorderThickness="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" MinWidth="50"> </Border> <controls:GridSplitter Grid.Column="1" VerticalAlignment="Stretch" Width="Auto" ></controls:GridSplitter> <Border BorderBrush="Blue" BorderThickness="1" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Grid.Column="2" MinWidth="50"></Border> </Grid> </UserControl>

  Read the article

• Why do bind1st and bind2nd require constant function objects?

  - by rlbond

  So, I was writing a C++ program which would allow me to take control of the entire world. I was all done writing the final translation unit, but I got an error: error C3848: expression having type 'const `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>' would lose some const-volatile qualifiers in order to call 'void `anonymous-namespace'::ElementAccumulator<T,BinaryFunction>::operator ()(const point::Point &,const int &)' with [ T=SideCounter, BinaryFunction=std::plus<int> ] c:\program files (x86)\microsoft visual studio 9.0\vc\include\functional(324) : while compiling class template member function 'void std::binder2nd<_Fn2>::operator ()(point::Point &) const' with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] c:\users\****\documents\visual studio 2008\projects\TAKE_OVER_THE_WORLD\grid_divider.cpp(361) : see reference to class template instantiation 'std::binder2nd<_Fn2>' being compiled with [ _Fn2=`anonymous-namespace'::ElementAccumulator<SideCounter,std::plus<int>> ] I looked in the specifications of binder2nd and there it was: it took a const AdaptibleBinaryFunction. So, not a big deal, I thought. I just used boost::bind instead, right? Wrong! Now my take-over-the-world program takes too long to compile (bind is used inside a template which is instantiated quite a lot)! At this rate, my nemesis is going to take over the world first! I can't let that happen -- he uses Java! So can someone tell me why this design decision was made? It seems like an odd decision. I guess I'll have to make some of the elements of my class mutable for now...

  Read the article

• Unable to get values in ftl from value stack in custom Result Type

  - by Nagadev

  Hello, I am unable retrieve value from value stack in FTL file. Here is the code. Action class holds a property called 'name' private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } public String execute(){ setName("From value stack .. "); return SUCCESS; } FTL code: ${name} Custom result Type deExecute Method Configuration configuration = new Configuration(); String templatePath = "/ftl"; ServletContext context = ServletActionContext.getServletContext(); configuration.setServletContextForTemplateLoading(context, templatePath); configuration.setObjectWrapper(new DefaultObjectWrapper()); Template template = configuration.getTemplate("sample.ftl"); OutputStreamWriter out = new OutputStreamWriter(System.out); template.process(ActionContext.getContext().getValueStack(), out); I am passing the value Stack which contains recently executed Action as well. But FTL is throwing an exception Expression name is undefined on line 1, column 3 in sample.ftl I tried with passing session instead of value stack and I could get the value in FTL. Please suggest me a way to get values from Action class to FTL from value stack. Thanks inadvance.

  Read the article

• Differences between Assembly Code output of the same program

  - by ultrajohn

  I have been trying to replicate the buffer overflow example3 from this article aleph one I'm doing this as a practice for a project in a computer security course i'm taking so please, I badly need your help. I've been the following the example, performing the tasks as I go along. My problem is the assembly code dumped by gdb in my computer (i'm doing this on a debian linux image running on VM Ware) is different from that of the example in the article. There are some constructs which I find confusing. Here is the one from my computer: here is the one from the article... Dump of assembler code for function main: 0x8000490 <main>: pushl %ebp 0x8000491 <main+1>: movl %esp,%ebp 0x8000493 <main+3>: subl $0x4,%esp 0x8000496 <main+6>: movl $0x0,0xfffffffc(%ebp) 0x800049d <main+13>: pushl $0x3 0x800049f <main+15>: pushl $0x2 0x80004a1 <main+17>: pushl $0x1 0x80004a3 <main+19>: call 0x8000470 <function> 0x80004a8 <main+24>: addl $0xc,%esp 0x80004ab <main+27>: movl $0x1,0xfffffffc(%ebp) 0x80004b2 <main+34>: movl 0xfffffffc(%ebp),%eax 0x80004b5 <main+37>: pushl %eax 0x80004b6 <main+38>: pushl $0x80004f8 0x80004bb <main+43>: call 0x8000378 <printf> 0x80004c0 <main+48>: addl $0x8,%esp 0x80004c3 <main+51>: movl %ebp,%esp 0x80004c5 <main+53>: popl %ebp 0x80004c6 <main+54>: ret 0x80004c7 <main+55>: nop As you can see, there are differences between the two. I'm confuse and I can't understand totally the assembly code from my computer. I would like to know the differences between the two. How is pushl different from push, mov vs movl , and so on... what does the expression 0xhexavalue(%register) means? I am sorry If I'm asking a lot, But I badly need your help. Thanks for the help really...

  Read the article

• d2: assigning ranges/iterators to array slices

  - by modchan

  Consider following code: enum size = 16; double[size] arr1 = [...]; double[size] arr2 = [...]; process = (double x) { return (x + 1); }; arr2[] = map!(process)(arr1[]); // here I have trouble converting results of map back to my plain array. Problem applies not only to map, but also to take, repeat and all those fine tools from std.algorithm and std.range that operate on ranges. On this assignment, I get Error: cannot implicitly convert expression (map(arr1[])) of type Result to double[]. How can I evaluate range to array without using uint i = 0; foreach (x; map!(process)(arr1[])) { arr2[i] = x; i++; } ? Additionally, can someone please explain, why I must call map!(process)(arr1[]) instead of map!(process)(arr1) with static arrays? Shouldn't static arrays be compatible with dynamic for means of iteration, or I don't get something? Also, it seems that straightforward enumeration syntax foreach (index, item; sequence) does not work for ranges - are there workarounds? I guess the reason is the same as why ranges cannot be assigned to array slices.

  Read the article

• Calculate the year for ending month/day?

  - by Dave Jarvis

  Given: Start Year Start Month & Start Day End Month & End Day What SQL statement results in TRUE if a date lands between the Start and End days? 1st example: Start Date = 11-22 End Date = 01-17 Start Year = 2009 Specific Date = 2010-01-14 TRUE 2nd example: Start Date = 11-22 End Date = 11-16 Start Year = 2009 Specific Date = 2010-11-20 FALSE 3rd example: Start Date = 02-25 End Date = 03-19 Start Year = 2004 Specific Date = 2004-02-29 TRUE I was thinking of using the MySQL functions datediff and sign plus a CASE condition to determine whether the year wraps, but it seems rather expensive. Am looking for a simple, efficient calculation. Update 1 The problem is the end date cannot simply use the year. The year must be increased if the end month/day combination happens before the start date. The start date is easy: Start Date = date( concat_ws( '-', year, Start Month, Start Day ) ) The end date is not so simple. Update 2 Here is what I was thinking about for obtaining the end year: end_year = case sign( diff( date( concat_ws( year, start_month, start_day ) ), date( concat_ws( year, end_month, end_day ) ) ) ) when -1 then Start_Year + 1 else Start_Year end case Then wrap that expression (once syntactically correct) inside of another date, followed by BETWEEN statement. Update 3 To clear up some confusion: there is no end year. The end year must be calculated. Thank you!

  Read the article

• What's the best way to resolve this scope problem?

  - by Peter Stewart

  I'm writing a program in python that uses genetic techniques to optimize expressions. Constructing and evaluating the expression tree is the time consumer as it can happen billions of times per run. So I thought I'd learn enough c++ to write it and then incorporate it in python using cython or ctypes. I've done some searching on stackoverflow and learned a lot. This code compiles, but leaves the pointers dangling. I tried 'this_node = new Node(...' . It didn't seem to work. And I'm not at all sure how I'd delete all the references as there would be hundreds. I'd like to use variables that stay in scope, but maybe that's not the c++ way. What is the c++ way? class Node { public: char *cargo; int depth; Node *left; Node *right; } Node make_tree(int depth) { depth--; if(depth <= 0) { Node tthis_node("value",depth,NULL,NULL); return tthis_node; } else { Node this_node("operator" depth, &make_tree(depth), &make_tree(depth)); return this_node; } };

  Read the article

• Is there a practical benefit to casting a NULL pointer to an object and calling one of its member fu

  - by zdawg

  Ok, so I know that technically this is undefined behavior, but nonetheless, I've seen this more than once in production code. And please correct me if I'm wrong, but I've also heard that some people use this "feature" as a somewhat legitimate substitute of a lacking aspect of the current C++ standard, namely, the inability to obtain the address (well, offset really) of a member function. For example, this is out of a popular implementation of a PCRE (Perl-compatible Regular Expression) library: #ifndef offsetof #define offsetof(p_type,field) ((size_t)&(((p_type *)0)->field)) #endif One can debate whether the exploitation of such a language subtlety in a case like this is valid or not, or even necessary, but I've also seen it used like this: struct Result { void stat() { if(this) // do something... else // do something else... } }; // ...somewhere else in the code... ((Result*)0)->stat(); This works just fine! It avoids a null pointer dereference by testing for the existence of this, and it does not try to access class members in the else block. So long as these guards are in place, it's legitimate code, right? So the question remains: Is there a practical use case, where one would benefit from using such a construct? I'm especially concerned about the second case, since the first case is more of a workaround for a language limitation. Or is it? PS. Sorry about the C-style casts, unfortunately people still prefer to type less if they can.

  Read the article

• Silverlight MVVM Confusion: Updating Image Based on State

  - by senfo

  I'm developing a Silverlight application and I'm trying to stick to the MVVM principals, but I'm running into some problems changing the source of an image based on the state of a property in the ViewModel. For all intents and purposes, you can think of the functionality I'm implementing as a play/pause button for an audio app. When in the "Play" mode, IsActive is true in the ViewModel and the "Pause.png" image on the button should be displayed. When paused, IsActive is false in the ViewModel and "Play.png" is displayed on the button. Naturally, there are two additional images to handle when the mouse hovers over the button. I thought I could use a Style Trigger, but apparently they're not supported in Silverlight. I've been reviewing a forum post with a question similar to mine where it's suggested to use the VisualStateManager. While this might help with changing the image for hover/normal states, the part missing (or I'm not understanding) is how this would work with a state set via the view model. The post seems to apply only to events rather than properties of the view model. Having said that, I also haven't successfully completed the normal/hover affects, either. Below is my Silverlight 4 XAML. It should also probably be noted I'm working with MVVM Light. <UserControl x:Class="Foo.Bar.MyUserControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" mc:Ignorable="d" d:DesignHeight="100" d:DesignWidth="200"> <UserControl.Resources> <Style x:Key="MyButtonStyle" TargetType="Button"> <Setter Property="IsEnabled" Value="true"/> <Setter Property="IsTabStop" Value="true"/> <Setter Property="Background" Value="#FFA9A9A9"/> <Setter Property="Foreground" Value="#FF000000"/> <Setter Property="MinWidth" Value="5"/> <Setter Property="MinHeight" Value="5"/> <Setter Property="Margin" Value="0"/> <Setter Property="HorizontalAlignment" Value="Left" /> <Setter Property="HorizontalContentAlignment" Value="Center"/> <Setter Property="VerticalAlignment" Value="Top" /> <Setter Property="VerticalContentAlignment" Value="Center"/> <Setter Property="Cursor" Value="Hand"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="Button"> <Grid> <Image Source="/Foo.Bar;component/Resources/Icons/Bar/Play.png"> <VisualStateManager.VisualStateGroups> <VisualStateGroup x:Name="Active"> <VisualState x:Name="MouseOver"> <Storyboard> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Source" Storyboard.TargetName="/Foo.Bar;component/Resources/Icons/Bar/Play_Hover.png" /> </Storyboard> </VisualState> </VisualStateGroup> </VisualStateManager.VisualStateGroups> </Image> </Grid> </ControlTemplate> </Setter.Value> </Setter> </Style> </UserControl.Resources> <Grid x:Name="LayoutRoot" Background="White"> <Button Style="{StaticResource MyButtonStyle}" Command="{Binding ChangeStatus}" Height="30" Width="30" /> </Grid> </UserControl> What is the proper way to update images on buttons with the state determined by the view model? Update I changed my Button to a ToggleButton hoping I could use the Checked state to differentiate between play/pause. I practically have it, but I ran into one additional problem. I need to account for two states at the same time. For example, Checked Normal/Hover and Unchecked Normal/Hover. Following is my updated XAML: <UserControl x:Class="Foo.Bar.MyUserControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" mc:Ignorable="d" d:DesignHeight="100" d:DesignWidth="200"> <UserControl.Resources> <Style x:Key="MyButtonStyle" TargetType="ToggleButton"> <Setter Property="IsEnabled" Value="true"/> <Setter Property="IsTabStop" Value="true"/> <Setter Property="Background" Value="#FFA9A9A9"/> <Setter Property="Foreground" Value="#FF000000"/> <Setter Property="MinWidth" Value="5"/> <Setter Property="MinHeight" Value="5"/> <Setter Property="Margin" Value="0"/> <Setter Property="HorizontalAlignment" Value="Left" /> <Setter Property="HorizontalContentAlignment" Value="Center"/> <Setter Property="VerticalAlignment" Value="Top" /> <Setter Property="VerticalContentAlignment" Value="Center"/> <Setter Property="Cursor" Value="Hand"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="ToggleButton"> <Grid> <VisualStateManager.VisualStateGroups> <VisualStateGroup x:Name="CommonStates"> <VisualState x:Name="Normal"> <Storyboard> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="Pause"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Collapsed</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="MouseOver"> <Storyboard> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="PlayHover"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Visible</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="Play"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Collapsed</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> </Storyboard> </VisualState> </VisualStateGroup> <VisualStateGroup x:Name="CheckStates"> <VisualState x:Name="Checked"> <Storyboard> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="Pause"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Visible</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="Play"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Collapsed</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)" Storyboard.TargetName="PlayHover"> <DiscreteObjectKeyFrame KeyTime="0"> <DiscreteObjectKeyFrame.Value> <Visibility>Collapsed</Visibility> </DiscreteObjectKeyFrame.Value> </DiscreteObjectKeyFrame> </ObjectAnimationUsingKeyFrames> </Storyboard> </VisualState> <VisualState x:Name="Unchecked" /> </VisualStateGroup> </VisualStateManager.VisualStateGroups> <Image x:Name="Play" Source="/Foo.Bar;component/Resources/Icons/Bar/Play.png" /> <Image x:Name="Pause" Source="/Foo.Bar;component/Resources/Icons/Bar/Pause.png" Visibility="Collapsed" /> <Image x:Name="PlayHover" Source="/Foo.Bar;component/Resources/Icons/Bar/Play_Hover.png" Visibility="Collapsed" /> <Image x:Name="PauseHover" Source="/Foo.Bar;component/Resources/Icons/Bar/Pause_Hover.png" Visibility="Collapsed" /> </Grid> </ControlTemplate> </Setter.Value> </Setter> </Style> </UserControl.Resources> <Grid x:Name="LayoutRoot" Background="White"> <ToggleButton Style="{StaticResource MyButtonStyle}" IsChecked="{Binding IsPlaying}" Command="{Binding ChangeStatus}" Height="30" Width="30" /> </Grid> </UserControl>

  Read the article

• Asterisk: Dropping calls with an "ast_yyerror"

  - by Nick

  I'm having an issue where asterisk will play our greeting to the caller, and then drop the call instead of making our phones ring. The bit of information I could find said it was caused by an error in evaluating a dialplan expression. I'm thinking it's this line: exten = START,n,GotoIf($[${FORCE_CLOSED}=TRUE]?CLOSED,1) But I'm not sure what's wrong with it. I see the following error on the console: [Apr 4 16:29:49] WARNING[27038]: ast_expr2.fl:459 ast_yyerror: ast_yyerror(): syntax error: syntax error, unexpected '=', expecting $end; Input:=TRUE^ Surrounding Console output: -- Executing [START@AGInbound:1] Answer("IAX2/AtlantaTeliax-10086", "") in new stack -- Executing [START@AGInbound:2] BackGround("IAX2/AtlantaTeliax-10086", 0000_AG_THANK_YOU_FOR_CALLING_AG") in new stack -- Playing '0000_AG_THANK_YOU_FOR_CALLING_AG.slin' (language 'en') [Apr 4 16:29:49] WARNING[27038]: ast_expr2.fl:459 ast_yyerror: ast_yyerror(): syntax error: syntax error, unexpected '=', expecting $end; Input: =TRUE ^ [Apr 4 16:29:49] WARNING[27038]: ast_expr2.fl:463 ast_yyerror: If you have questions, please refer to doc/tex/channelvariables.tex in the asterisk source. -- Executing [START@AGInbound:3] GotoIf("IAX2/AtlantaTeliax-10086", "?CLOSED,1") in new stack -- Executing [START@AGInbound:4] GotoIfTime("IAX2/AtlantaTeliax-10086", "9:30-17:0|mon-fri|*|*?OPEN,1") in new stack -- Executing [START@AGInbound:5] GotoIfTime("IAX2/AtlantaTeliax-10086", "10:0-18:30|sat|*|*?OPEN,1") in new stack -- Executing [START@AGInbound:6] GotoIfTime("IAX2/AtlantaTeliax-10086", "12:0-17:0|sun|*|*?OPEN,1") in new stack Relevant lines from the dial plan: exten = START,1,Answer() exten = START,n,Background(0000_AG_THANK_YOU_FOR_CALLING_AG) ; See if we're open ; Force Closed if no one's going to be answering exten = START,n,GotoIf($[${FORCE_CLOSED}=TRUE]?CLOSED,1) exten = START,n,GotoIfTime(${AG_WEEKDAY_OPEN_HOUR}:${AG_WEEKDAY_OPEN_MIN}-${AG$ exten = START,n,GotoIfTime(${AG_SATURDAY_OPEN_HOUR}:${AG_SATURDAY_OPEN_MIN}-${$ exten = START,n,GotoIfTime(${AG_SUNDAY_OPEN_HOUR}:${AG_SUNDAY_OPEN_MIN}-${AG_S$ ; ...and we're not. But maybe the time of day has been overridden? exten = START,n,GotoIf($[${OVERRIDE_TIME_OF_DAY}=TRUE]?OPEN,1) ; No override... We're definatly closed. exten = START,n,Goto(CLOSED,1)

  Read the article

• Project management: Implementing custom errors in VS compilation process

  - by David Lively

  Like many architects, I've developed coding standards through years of experience to which I expect my developers to adhere. This is especially a problem with the crowd that believes that three or four years of experience makes you a senior-level developer.Approaching this as a training and code review issue has generated limited success. So, I was thinking that it would be great to be able to add custom compile-time errors to the build process to more strictly enforce this and other guidelines. For instance, we use stored procedures for ALL database access, which provides procedure-level security, db encapsulation (table structure is hidden from the app), and other benefits. (Note: I am not interested in starting a debate about this.) Some developers prefer inline SQL or parametrized queries, and that's fine - on their own time and own projects. I'd like a way to add a compilation check that finds, say, anything that looks like string sql = "insert into some_table (col1,col2) values (@col1, @col2);" and generates an error or, in certain circumstances, a warning, with a message like Inline SQL and parametrized queries are not permitted. Or, if they use the var keyword var x = new MyClass(); Variable definitions must be explicitly typed. Do Visual Studio and MSBuild provide a way to add this functionality? I'm thinking that I could use a regular expression to find unacceptable code and generate the correct error, but I'm not sure what, from a performance standpoint, is the best way to to integrate this into the build process. We could add a pre- or post-build step to run a custom EXE, but how can I return line- and file-specifc errors? Also, I'd like this to run after compilation of each file, rather than post-link. Is a regex the best way to perform this type of pattern matching, or should I go crazy and run the code through a C# parser, which would allow node-level validation via the parse tree? I'd appreciate suggestions and tales of prior experience.

  Read the article

< Previous Page | 444 445 446 447 448 449 450 451 452 453 454 455  | Next Page >