Search Results

Search found 4077 results on 164 pages for 'throw'.

Page 135/164 | < Previous Page | 131 132 133 134 135 136 137 138 139 140 141 142  | Next Page >

  • Porting Perl to C++ `print "\x{2501}" x 12;`

    - by jippie
    I am porting a program from Perl to C++ as a learning objective. I arrived at a routine that draws a table with commands like the following: Perl: print "\x{2501}" x 12; And it draws 12 times a '?' ("box drawings heavy horizontal"). Now I figured out part of the problem already: Perl: \x{}, \x00 Hexadecimal escape sequence; C++: \unnnn To print a single Unicode character: C++: printf( "\u250f\n" ); But does C++ have a smart equivalent for the 'x' operator or would it come down to a for loop? UPDATE Let me include the full source code I am trying to compile with the proposed solution. The compiler does throw an errors: g++ -Wall -Werror project.cpp -o project project.cpp: In function ‘int main(int, char**)’: project.cpp:38:3: error: ‘string’ is not a member of ‘std’ project.cpp:38:15: error: expected ‘;’ before ‘s’ project.cpp:39:3: error: ‘cout’ is not a member of ‘std’ project.cpp:39:16: error: ‘s’ was not declared in this scope #include <stdlib.h> #include <stdint.h> #include <stdio.h> #include <string.h> int main ( int argc, char *argv[] ) { if ( argc != 2 ) { fprintf( stderr , "usage: %s matrix\n", argv[0] ); exit( 2 ); } else { //std::string s(12, "\u250f" ); std::string s(12, "u" ); std::cout << s; } }

    Read the article

  • In Javascript, what's better than try/catch for exiting an outer scope?

    - by gruseom
    In Javascript, I sometimes want to return a value from a scope that isn't the current function. It might be a block of code within the function, or it might be an enclosing function as in the following example, which uses a local function to recursively search for something. As soon as it finds a solution, the search is done and the whole thing should just return. Unfortunately, I can't think of a simpler way to do this than by hacking try/catch for the purpose: function solve(searchSpace) { var search = function (stuff) { solution = isItSolved(stuff); if (solution) { throw solution; } else { search(narrowThisWay(stuff)); search(narrowThatWay(stuff)); }; }; try { return search(searchSpace); } catch (solution) { return solution; }; }; I realize one could assign the solution to a local variable and then check it before making another recursive call, but my question is specifically about transfer of control. Is there a better way than the above? Perhaps involving label/break?

    Read the article

  • How good idea is it to use code contracts in Visual Studio 2010 Professional (ie. no static checking

    - by Lasse V. Karlsen
    I create class libraries, some which are used by others around the world, and now that I'm starting to use Visual Studio 2010 I'm wondering how good idea it is for me to switch to using code contracts, instead of regular old-style if-statements. ie. instead of this: if (String.IsNullOrWhiteSpace(fileName)) throw new ArgumentNullException("fileName"); (yes, I know, if it is whitespace, it isn't strictly null) use this: Contract.Requires(!String.IsNullOrWhiteSpace(fileName)); The reason I'm asking is that I know that the static checker is not available to me, so I'm a bit nervous about some assumptions that I make, that the compiler cannot verify. This might lead to the class library not compiling for someone that downloads it, when they have the static checker. This, coupled with the fact that I cannot even reproduce the problem, would make it tiresome to fix, and I would gather that it doesn't speak volumes to the quality of my class library if it seemingly doesn't even compile out of the box. So I have a few questions: Is the static checker on by default if you have access to it? Or is there a setting I need to switch on in the class library (and since I don't have the static checker, I won't) Are my fears unwarranted? Is the above scenario a real problem? Any advice would be welcome.

    Read the article

  • Recursion Problem in PHP

    - by streetparade
    I need to create a valid xml from a given array(); My Method looks like this, protected function array2Xml($array) { $xml = ""; if(is_array($array)) { foreach($array as $key=>$value) { $xml .= "<$key>"; if(is_array($value)) { $xml .= $this->array2Xml($value); } $xml .= "</$key>"; } return $xml; } else { throw new Exception("in valid"); } } protected function createValidXMLfromArray($array,$node) { $xml = '<?xml version="1.0" encoding="ISO-8859-1"?>'; $xmlArray = $this->array2Xml($array); $xml .= "<$node>$xmlArray</$node>"; return $xml; } if i execute the above i just get keys with empty values; like <node> <name></name> </node> What i need is if i pass this array("name"=>"test","value"=>array("test1"=>33,"test2"=>40)); that it return this <node> <name>test</name> <value> <test1>33</test1> <test2>40</test2> </value> </node> Where is the error what did i wrong in the above recursion?

    Read the article

  • Stored procedure or function expects parameter which is not supplied

    - by user2920046
    I am trying to insert data into a SQL Server database by calling a stored procedure, but I am getting the error Procedure or function 'SHOWuser' expects parameter '@userID', which was not supplied. My stored procedure is called "SHOWuser". I have checked it thoroughly and no parameters is missing. My code is: public void SHOWuser(string userName, string password, string emailAddress, List preferences) { SqlConnection dbcon = new SqlConnection(conn); try { SqlCommand cmd = new SqlCommand(); cmd.Connection = dbcon; cmd.CommandType = System.Data.CommandType.StoredProcedure; cmd.CommandText = "SHOWuser"; cmd.Parameters.AddWithValue("@userName", userName); cmd.Parameters.AddWithValue("@password", password); cmd.Parameters.AddWithValue("@emailAddress", emailAddress); dbcon.Open(); int i = Convert.ToInt32(cmd.ExecuteScalar()); cmd.Parameters.Clear(); cmd.CommandText = "tbl_pref"; foreach (int preference in preferences) { cmd.Parameters.Clear(); cmd.Parameters.AddWithValue("@userID", Convert.ToInt32(i)); cmd.Parameters.AddWithValue("@preferenceID", Convert.ToInt32(preference)); cmd.ExecuteNonQuery(); } } catch (Exception) { throw; } finally { dbcon.Close(); } and the stored procedure is: ALTER PROCEDURE [dbo].[SHOWuser] -- Add the parameters for the stored procedure here ( @userName varchar(50), @password nvarchar(50), @emailAddress nvarchar(50) ) AS BEGIN INSERT INTO tbl_user(userName,password,emailAddress) values(@userName,@password,@emailAddress) select tbl_user.userID,tbl_user.userName,tbl_user.password,tbl_user.emailAddress, stuff((select ',' + preferenceName from tbl_pref_master inner join tbl_preferences on tbl_pref_master.preferenceID = tbl_preferences.preferenceID where tbl_preferences.userID=tbl_user.userID FOR XML PATH ('')),1,1,' ' ) AS Preferences from tbl_user SELECT SCOPE_IDENTITY(); END Pls help, Thankx in advance...

    Read the article

  • Why my linux signal handler run only once

    - by Henry Fané
    #include <iostream> #include <signal.h> #include <fenv.h> #include <string.h> void signal_handler(int sig, siginfo_t *siginfo, void* context) { std::cout << " signal_handler " << fetestexcept(FE_ALL_EXCEPT) << std::endl; throw "exception"; } void divide() { float a = 1000., b = 0., c, f = 1e-300; c = a / b; std::cout << c << " and f = " << f << std::endl; } void init_sig_hanlder() { feenableexcept(FE_ALL_EXCEPT); struct sigaction sa, initial_sa; sa.sa_sigaction = &signal_handler ; sigemptyset( &sa.sa_mask ) ; sa.sa_flags = SA_SIGINFO; // man sigaction(3) // allows for void(*)(int,siginfo_t*,void*) handler sigaction(SIGFPE, &sa, &initial_sa); } int main(int argc, char** argv) { init_sig_hanlder(); while(true) { try { sleep(1); divide(); } catch(const char * a) { std::cout << "Exception in catch: " << a << std::endl; } catch(...) { std::cout << "Exception in ..." << std::endl; } } return 0; } Produce the following results on Linux/g++4.2: signal_handler 0 Exception in catch: exception inf and f = 0 inf and f = 0 inf and f = 0 inf and f = 0 So, signal handler is executed the first time but the next fp exception does not trigger the handler again. Where am I wrong ?

    Read the article

  • Bizzare Java invalid Assignment Operator Error

    - by Kay
    public class MaxHeap<T extends Comparable<T>> implements Heap<T>{ private T[] heap; private int lastIndex; private static final int defaultInitialCapacity = 25; public void add(T newItem) throws HeapException{ if (lastIndex < Max_Heap){ heap[lastIndex] = newItem; int place = lastIndex; int parent = (place – 1)/2; //ERROR HERE********** while ( (parent >=0) && (heap[place].compareTo(heap[parent])>0)){ T temp = heap[place]; heap[place] = heap[parent]; heap[parent] = temp; place = parent; parent = (place-1)/2; }else { throw new HeapException(“HeapException: Heap full”); } } } Eclipse complains that there is a: "Syntax error on token "Invalid Character", invalid AssignmentOperator" With the red line beneath the '(place-1)' There shouldn't be an error at all since it's just straight-forward arithmetic. Or is it not that simple?

    Read the article

  • Checked and Unchecked operators don't seem to be working when...

    - by flockofcode
    1) Is UNCHECKED operator in effect only when expression inside UNCHECKED context uses an explicit cast ( such as byte b1=unchecked((byte)2000); ) and when conversion to particular type can happen implicitly? I’m assuming this since the following expression throws a compile time error: byte b1=unchecked(2000); //compile time error 2) a) Do CHECKED and UNCHECKED operators work only when resulting value of an expression or conversion is of an integer type? I’m assuming this since in the first example ( where double type is being converted to integer type ) CHECKED operator works as expected: double m = double.MaxValue; b=checked((byte)m); // reports an exception , while in second example ( where double type is being converted to a float type ) CHECKED operator doesn’t seem to be working. since it doesn't throw an exception: double m = double.MaxValue; float f = checked((float)m); // no exception thrown b) Why don’t the two operators also work with expressions where type of a resulting value is of floating-point type? 2) Next quote is from Microsoft’s site: The unchecked keyword is used to control the overflow-checking context for integral-type arithmetic operations and conversions I’m not sure I understand what exactly have expressions and conversions such as unchecked((byte)(100+200)); in common with integrals? Thank you

    Read the article

  • Merging two arrays in PHP

    - by Industrial
    Hi everyone, I am trying to create a new array from two current arrays. Tried array_merge, but it will not give me what I want. $array1 is a list of keys that I pass to a function. $array2 holds the results from that function, but doesn't contain any non-available resuls for keys. So, I want to make sure that all requested keys comes out with 'null':ed values, as according to the shown $result array. It goes a little something like this: $array1 = array('item1', 'item2', 'item3', 'item4'); $array2 = array( 'item1' => 'value1', 'item2' => 'value2', 'item3' => 'value3' ); Here's the result I want: $result = array( 'item1' => 'value1', 'item2' => 'value2', 'item3' => 'value3', 'item4' => '' ); It can be done this way, but I don't think that it's a good solution - I really don't like to take the easy way out and suppress PHP errors by adding @:s in the code. This sample would obviously throw errors since 'item4' is not in $array2, based on the example. foreach ($keys as $k => $v){ @$array[$v] = $items[$v]; } So, what's the fastest (performance-wise) way to accomplish the same result?

    Read the article

  • Get class constant names in php?

    - by user151841
    I have a php class with some class constants that indicate the status of an instance. When I'm using the class, after I run some methods on it, I do some checks to make sure that the status is what I expect it to be. For instance, after calling some methods, I expect the status to be MEANINGFUL_STATUS_NAME. $objInstance->method1(); $objInstance->method2(); if ( $objInstance->status !== class::MEANINGFUL_STATUS_NAME ) { throw new Exception("Status is wrong, should not be " . class::MEANINGFUL_STATUS_NAME . "."); } However, this gives me the exception message "Status is wrong, should not be 2" when what I really want to see is "Status is wrong, should not be MEANINGFUL_STATUS_NAME" So I've lost the meaningfulness of the constant name. I was thinking of making an 'translation table' array, so I can take the constant values and translate them back into their name, but this seems cumbersome. How should I translate this back, so I get an error message that gives me a better idea of what went wrong?

    Read the article

  • Passing mix of T and T[] to a Java varargs method

    - by rfalke
    Suppose you have a Java method void foobar(int id, String ... args) and want to pass both String arrays and Strings into the method. Like this String arr1[]={"adas", "adasda"}; String arr2[]={"adas", "adasda"}; foobar(0, "adsa", "asdas"); foobar(1, arr1); foobar(2, arr1, arr2); foobar(3, arr1, "asdas", arr2); In Python there is "*" for this. Is there some way better than such rather ugly helper method: static String[] concat(Object... args) { List<String> result = new ArrayList<String>(); for (Object arg : args) { if (arg instanceof String) { String s = (String) arg; result.add(s); } else if (arg.getClass().isArray() && arg.getClass().getComponentType().equals(String.class)) { String arr[] = (String[]) arg; for (String s : arr) { result.add(s); } } else { throw new RuntimeException(); } } return result.toArray(new String[result.size()]); } which allows foobar(4, concat(arr1, "asdas", arr2));

    Read the article

  • What is a good "Error Checking" Pattern (Java)?

    - by Jack
    I'll explain what I mean by input error checking. Say you have a function doSomething(x). If the function completes successfully doSomething does something and returns nothing. However, if there are errors I'd like to be notified. That is what I mean by error checking. I'm looking for, in general, the best way to check for errors. I've thought of the following solutions, each with a potential problem. Flag error checking. If doSomething(x) completes successfully return null. Otherwise, it returns a boolean or an error string. Problem: Side effects. Throwing an exception. Throw an exception if doSomething(x) encounters an error. Problem: If you are performing error checking for parameters only, throwing an IllegalArgumentExceptionseems inappropriate. Validating input prior to function call. If the error checking is only meant for the parameters of the function, then you can call a validator function before calling the doSomething(x) function. Problem: What if a client of the class forgets to call the validator function before calling doSomething(x)? I often encounter this problem and any help or a point in the right direction would be much appreciated.

    Read the article

  • Confused about std::runtime_error vs. std::logic_error

    - by David Gladfelter
    I recently saw that the boost program_options library throws a logic_error if the command-line input was un-parsable. That challenged my assumptions about logic_error vs. runtime_error. I assumed that logic errors (logic_error and its derived classes) were problems that resulted from internal failures to adhere to program invariants, often in the form of illegal arguments to internal API's. In that sense they are largely equivalent to ASSERT's, but meant to be used in released code (unlike ASSERT's which are not usually compiled into released code.) They are useful in situations where it is infeasible to integrate separate software components in debug/test builds or the consequences of a failure are such that it is important to give runtime feedback about the invalid invariant condition to the user. Similarly, I thought that runtime_errors resulted exclusively from runtime conditions outside of the control of the programmer: I/O errors, invalid user input, etc. However, program_options is obviously heavily (primarily?) used as a means of parsing end-user input, so under my mental model it certainly should throw a runtime_error in the case of bad input. Where am I going wrong? Do you agree with the boost model of exception typing?

    Read the article

  • A better solution than element.Elements("Whatever").First()?

    - by codeka
    I have an XML file like this: <SiteConfig> <Sites> <Site Identifier="a" /> <Site Identifier="b" /> <Site Identifier="c" /> </Sites> </SiteConfig> The file is user-editable, so I want to provide reasonable error message in case I can't properly parse it. I could probably write a .xsd for it, but that seems kind of overkill for a simple file. So anyway, when querying for the list of <Site> nodes, there's a couple of ways I could do it: var doc = XDocument.Load(...); var siteNodes = from siteNode in doc.Element("SiteConfig").Element("SiteUrls").Elements("Sites") select siteNode; But the problem with this is that if the user has not included the <SiteUrls> node (say) it'll just throw a NullReferenceException which doesn't really say much to the user about what actually went wrong. Another possibility is just to use Elements() everywhere instead of Element(), but that doesn't always work out when coupled with calls to Attribute(), for example, in the following situation: var siteNodes = from siteNode in doc.Elements("SiteConfig") .Elements("SiteUrls") .Elements("Sites") where siteNode.Attribute("Identifier").Value == "a" select siteNode; (That is, there's no equivalent to Attributes("xxx").Value) Is there something built-in to the framework to handle this situation a little better? What I would prefer is a version of Element() (and of Attribute() while we're at it) that throws a descriptive exception (e.g. "Looking for element <xyz> under <abc> but no such element was found") instead of returning null. I could write my own version of Element() and Attribute() but it just seems to me like this is such a common scenario that I must be missing something...

    Read the article

  • Implementing a Version check between an Abstract class and it's implementation

    - by Michael Stum
    I have this abstract class and concrete implementation (they are in different assemblies): public abstract class MyAbstractClass { private static readonly int MyAbstractClassVersion = 1; public abstract int ImplementedVersion { get; } protected MyAbstractClass() { CheckVersion(); } private void CheckVersion() { var message = string.Format( "MyAbstractClass implements Version {0}, concrete is Version {1}", RepositoryVersion, ImplementedVersion); if (!MyAbstractClassVersion.Equals(ImplementedVersion)) throw new InvalidOperationException(message); } } public class ConcreteClass : MyAbstractClass { public ConcreteClass() : base() { // ConcreteClass is guaranteed to have // a constructor that calls the base constructor // I just simplified the example } public override int ImplementedVersion { get { return 2; } } } As you see, I call CheckVersion() from the abstract constructor, to get rid of the "virtual member call in base constructor" message, but I am not sure if that's really the way to do it. Sure, it works, but that doesn't mean it will always work, will it? Also, I wonder if I can get the name of the Concrete Type from the CheckVersion() function? I know that adding new abstract members will force an error anyway (System.TypeLoadException) and I'm not sure if I want this type of strict Versioning, but I'm just curious how it would be done properly given only the abstract class and an implementation (I know I could do it by using interfaces and/or a Factory pattern).

    Read the article

  • Criteria for triggering garbage collection in .Net

    - by Kennet Belenky
    I've come across some curious behavior with regard to garbage collection in .Net. The following program will throw an OutOfMemoryException very quickly (after less than a second on a 32-bit, 2GB machine). The Foo finalizer is never called. class Foo { static Dictionary<Guid, WeakReference> allFoos = new Dictionary<Guid, WeakReference>(); Guid guid = Guid.NewGuid(); byte[] buffer = new byte[1000000]; static Random rand = new Random(); public Foo() { // Uncomment the following line and the program will run forever. // rand.NextBytes(buffer); allFoos[guid] = new WeakReference(this); } ~Foo() { allFoos.Remove(guid); } static public void Main(string args[]) { for (; ; ) { new Foo(); } } } If the rand.nextBytes line is uncommented, it will run ad infinitum, and the Foo finalizer is regularly invoked. Why is that? My best guess is that in the former case, either the CLR or the Windows VMM is lazy about allocating physical memory. The buffer never gets written to, so the physical memory is never used. When the address space runs out, the system crashes. In the latter case, the system runs out of physical memory before it runs out of address space, the GC is triggered and the objects are collected. However, here's the part I don't get. Assuming my theory is correct, why doesn't the GC trigger when the address space runs low? If my theory is incorrect, then what's the real explanation?

    Read the article

  • How can this Ambient Context become null?

    - by Mark Seemann
    Can anyone help me explain how TimeProvider.Current can become null in the following class? public abstract class TimeProvider { private static TimeProvider current = DefaultTimeProvider.Instance; public static TimeProvider Current { get { return TimeProvider.current; } set { if (value == null) { throw new ArgumentNullException("value"); } TimeProvider.current = value; } } public abstract DateTime UtcNow { get; } public static void ResetToDefault() { TimeProvider.current = DefaultTimeProvider.Instance; } } Observations All unit tests that directly reference TimeProvider also invokes ResetToDefault() in their Fixture Teardown. There is no multithreaded code involved. Once in a while, one of the unit tests fail because TimeProvider.Current is null (NullReferenceException is thrown). This only happens when I run the entire suite, but not when I just run a single unit test, suggesting to me that there is some subtle test interdependence going on. It happens approximately once every five or six test runs. When a failure occurs, it seems to be occuring in the first executed tests that involves TimeProvider.Current. More than one test can fail, but only one fails in a given test run. FWIW, here's the DefaultTimeProvider class as well: public class DefaultTimeProvider : TimeProvider { private readonly static DefaultTimeProvider instance = new DefaultTimeProvider(); private DefaultTimeProvider() { } public override DateTime UtcNow { get { return DateTime.UtcNow; } } public static DefaultTimeProvider Instance { get { return DefaultTimeProvider.instance; } } } I suspect that there's some subtle interplay going on with static initialization where the runtime is actually allowed to access TimeProvider.Current before all static initialization has finished, but I can't quite put my finger on it. Any help is appreciated.

    Read the article

  • Excel I have a .Net object compiled as a tlb but cant not access any methods apart from Dispose.

    - by Mark O'Grady
    Hi This is ongoing issue to something I posted yesterday. I have a .net object that I want to use in Excel. I have an existing VBA script that i need to alter to call this the object from. I have then converted the object to a TLB. I've not really touched on this area before so any help will be appreciated. I have created an interface [Guid("0F700B48-E0CA-446b-B87E-555BCC317D74"),InterfaceType(ComInterfaceType.InterfaceIsDual)] [ComVisible(true)] public interface IOfficeCOMInterface { [DispId(1)] void ResetOrder(); [DispId(2)] void SetDeliveryAddress(string PostalName, string AddressLine1, string AddressLine2, string AddressLine3, string AddressLine4, string PostCode, string CountryCode, string TelephoneNo, string FaxNo, string EmailAddress); } I have also created an class that inherits that object. [ClassInterface(ClassInterfaceType.None), ProgId("NAMESPACE.OfficeCOMInterface"), Guid("9D9723F9-8CF1-4834-BE69-C3FEAAAAB530"), ComVisible(true)] public class OfficeCOMInterface : IOfficeCOMInterface, IDisposable { public void ResetSOPOrder() { } public void SetDeliveryAddress(string PostalName, string AddressLine1, string AddressLine2, string AddressLine3, string AddressLine4, string PostCode, string CountryCode, string TelephoneNo, string FaxNo, string EmailAddress) { try { SalesOrder.AmendDeliveryAddress(PostalName, AddressLine1, AddressLine2, AddressLine3, AddressLine4, PostCode); MessageBox.Show("Delivery address set"); } catch (Exception ex) { throw ex; } } } I can't access the object methods apart from dispose, I guess IDisposable is working fine. Is there anything I need to my Interface?

    Read the article

  • issue with keychain and updates from app store

    - by xonegirlz
    I am having a very frustrating error. I have tested for an app upgrade by first installing the previous version (1.0.1) and then running version (1.0.2). Everything worked fine. I submitted the app and then I am getting issues people are getting crashes when they upgrade. I tried doing the same thing, which is installing the 1.0.1 and then install the binary on the app store, then it crashed. I looked at the console and crash logs and I get this: Jul 7 08:07:45 unknown MyApp[1429] <Warning>: KeychainUtils keychainValueForKey: - Error finding keychain value for key. Status code = -25300 Jul 7 08:07:45 unknown MyApp[1429] <Warning>: AccountSession readUserDataFromDisk - Error finding keychain value for key /var/mobile/Applications/997B32E7-6FFC-4696-9CAA-129BADE2FE64/Documents/instagram_json Jul 7 08:07:45 unknown MyApp[1429] <Warning>: UISegmentedControlStyleBezeled is deprecated. Please use a different style. Jul 7 08:07:45 unknown MyApp[1429] <Error>: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFDictionary setObject:forKey:]: attempt to insert nil value (key: username)' *** First throw call stack: (0x33ee688f 0x367e7259 0x33ee6789 0x33ee67ab 0x33e5368b 0x14fd99 0x152319 0x1530bb 0x170299 0x3270ec59 0x32711817 0x354e7dfb 0x354e7cd0) Jul 7 08:07:45 unknown UIKitApplication:com.firesnakelabs.pinstagram[0x14e4][1429] <Notice>: terminate called throwing an exception >

    Read the article

  • Is there a standard SQL Table design for overriding 'big picture' default values with lower level de

    - by RichardHowells
    Here's an example. Suppose we are trying to calculate a service charge. Say sales in the USA attract a 10 dollar charge, sales in the UK attract a 20 dollar charge So far it's easy - we are starting to imagine a table that lists charges by country. Now lets assume that Alaska and Hawaii are treated as special cases they are both 15 dollars That suggests a table with states, Alaska and Hawaii are charged at 15, but presumably we need 48 (redundant) rows all saying 10. This gives us a maintainance problem, our user only wants to type 10 once NOT 48 times. It does not sit well with the UK either. The UK does not have states. Suppose we throw in another couple of cross cutting rules. If you order by phone there is a 10% supplement on the charge. If you order via the web there is a 10% discount. But for some reason best known to the owners of the business the web/phone supplement/discount are not applied in Hawaii. It seems to me that this is quite a common kind of problem and there is probably a well known arrangement of tables to store the data. Most cases get handled by broad brush answers, but there are some very detailed low level variations that give rise to a huge number of theoretical combinations, most of which are not used.

    Read the article

  • Convert C# (with typed events) to VB.NET

    - by Steven
    I have an ASPX page (with VB Codebehind). I would like to extend the GridView class to show the header / footer when no rows are returned. I found a C# example online (link) (source). However, I cannot convert it to VB because it uses typed events (which are not legal in VB). I have tried several free C# to VB.NET converters online, but none have worked. Please convert the example to VB.NET or provide an alternate method of extending the GridView class. Notes / Difficulties: If you get an error with DataView objects, specify the type as System.Data.DataView and the type comparison could be the following: If data.[GetType]() Is GetType(System.Data.DataView) Then Since the event MustAddARow cannot have a type in VB (and RaiseEvent event doesn't have a return value), how can I compare it to Nothing in the function OnMustAddARow()? EDIT: The following is a sample with (hopefully) relevant code to help answer the question. namespace AlwaysShowHeaderFooter { public delegate IEnumerable MustAddARowHandler(IEnumerable data); public class GridViewAlwaysShow : GridView { ////////////////////////////////////// // Various member functions omitted // ////////////////////////////////////// protected IEnumerable OnMustAddARow(IEnumerable data) { if (MustAddARow == null) { throw new NullReferenceException("The datasource has no rows. You must handle the \"MustAddARow\" Event."); } return MustAddARow(data); } public event MustAddARowHandler MustAddARow; } }

    Read the article

  • Can you explain this generics behavior and if I have a workaround?

    - by insta
    Sample program below: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace GenericsTest { class Program { static void Main(string[] args) { IRetrievable<int, User> repo = new FakeRepository(); Console.WriteLine(repo.Retrieve(35)); } } class User { public int Id { get; set; } public string Name { get; set; } } class FakeRepository : BaseRepository<User>, ICreatable<User>, IDeletable<User>, IRetrievable<int, User> { // why do I have to implement this here, instead of letting the // TKey generics implementation in the baseclass handle it? //public User Retrieve(int input) //{ // throw new NotImplementedException(); //} } class BaseRepository<TPoco> where TPoco : class,new() { public virtual TPoco Create() { return new TPoco(); } public virtual bool Delete(TPoco item) { return true; } public virtual TPoco Retrieve<TKey>(TKey input) { return null; } } interface ICreatable<TPoco> { TPoco Create(); } interface IDeletable<TPoco> { bool Delete(TPoco item); } interface IRetrievable<TKey, TPoco> { TPoco Retrieve(TKey input); } } This sample program represents the interfaces my actual program uses, and demonstrates the problem I'm having (commented out in FakeRepository). I would like for this method call to be generically handled by the base class (which in my real example is able to handle 95% of the cases given to it), allowing for overrides in the child classes by specifying the type of TKey explicitly. It doesn't seem to matter what parameter constraints I use for the IRetrievable, I can never get the method call to fall through to the base class. Also, if anyone can see an alternate way to implement this kind of behavior and get the result I'm ultimately looking for, I would be very interested to see it. Thoughts?

    Read the article

  • Better way to catch trouble points

    - by mac
    User submits a CSV file which is consumed by a program. Values which are used throughout the program come from the CSV, natually if values are missed it is a problem. Below is my solution. Ip on top private List<String> currentFieldName = new ArrayList<String>(); As part of the method: try { setCurrentFieldName("Trim Space"); p.setTrimSpace(currentLineArray[dc.getTRIM_POSITION()].equals("yes") ? true : false); setCurrentFieldName("Ignore Case"); p.setIgnoreCase(currentLineArray[dc.getIGNORE_CASE_POSITION()].equals("yes") ? true : false); } catch (NullPointerException e) { throw new InputSpreadsheetValueUnassignedException("\"Type\" field not set: " + currentFieldName); } And the method which keeps track of a current field being looked at: private void setCurrentFieldName(String fieldName) { currentFieldName.clear(); currentFieldName.add(fieldName); } The idea there is that if user fails to submit value and i will end up getting null, before throwing an exception, i will know what value was not assigned. So, this being said, specific questions: Is what i have shown below an acceptable solution? Can you suggest something more elegant?

    Read the article

  • Returning JSON or XML for Exceptions in Jersey

    - by Dominic
    My goal is to have an error bean returned on a 404 with a descriptive message when a object is not found, and return the same MIME type that was requested. I have a look up resource, which will return the specified object in XML or JSON based on the URI (I have setup the com.sun.jersey.config.property.resourceConfigClass servlet parameter so I dont need the Accept header. My JAXBContextResolver has the ErrorBean.class in its list of types, and the correct JAXBContext is returned for this class because I can see in the logs). eg: http://foobar.com/rest/locations/1.json @GET @Path("{id}") @Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML}) public Location getCustomer(@PathParam("id") int cId) { //look up location from datastore .... if (location == null) { throw new NotFoundException("Location" + cId + " is not found"); } } And my NotFoundException looks like this: public class NotFoundException extends WebApplicationException { public NotFoundException(String message) { super(Response.status(Response.Status.NOT_FOUND). entity(new ErrorBean( message, Response.Status.NOT_FOUND.getStatusCode() ) .build()); } } The ErrorBean is as follows: @XmlRootElement(name = "error") public class ErrorBean { private String errorMsg; private int errorCode; //no-arg constructor, property constructor, getter and setters ... } However, I'm always getting a 204 No Content response when I try this. I have hacked around, and if I return a string and specify the mime type this works fine: public NotFoundException(String message) { super(Response.status(Response.Status.NOT_FOUND). entity(message).type("text/plain").build()); } I have also tried returning an ErrorBean as a resource. This works fine: {"errorCode":404,"errorMsg":"Location 1 is not found!"}

    Read the article

  • Does Spring MVC form submit data bind children objects automagically?

    - by predhme
    I have a data model that is something like this: public class Report { // report owner private User user; ... typical getter setter ... } public class User { ... omitted for clarity } What happens is when a report is created, the current user is set to the report user object. When the report is edited, the spring controller handling the POST request is receiving a report where the user object is null. Here is what my controller looks like: @Controller @RequestMapping("/report") public class ReportController { @RequestMapping(value = "/edit/{id}", method = RequestMethod.GET) public String editReport(@PathVariable Long id, Model model) { Report r = backend.getReport(id); // fully loads object model.addAttribute("report", report); return "report/edit"; } @RequestMapping(value = "/edit/{id}", method = RequestMethod.POST) public String process(@ModelAttribute("report") Report r) { backend.save(r); return "redirect:/report/show" + r.getId(); } } I ran things throw the debugger and it looks like in the editReport method the model object is storing the fully loaded report object (I can see the user inside the report). On the form jsp I can do the following: ${report.user.username} and the correct result is rendered. However, when I look at the debugger in the process method, the passed in Report r has a null user. I don't need to do any special data binding to ensure that information is retained do I?

    Read the article

< Previous Page | 131 132 133 134 135 136 137 138 139 140 141 142  | Next Page >