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  • Problem using pantheios file stock back end

    - by Tanuj
    I am trying to use pantheios file stock back end to log from my dll in c++. The file gets created but nothing gets written to the file. Here is a snippet of my code if (pantheios::pantheios_init() < 0) { MessageBox(NULL, "Init Failed", "fvm", MB_OK); }else { MessageBox(NULL, "Init Passed", "fvm", MB_OK); pantheios::log_INFORMATIONAL("Logger enabled!"); } DWORD pid = GetCurrentProcessId(); sprintf_s(moduleName, sizeof(moduleName), "C:\\%d.log", pid); pantheios_be_file_setFilePath(moduleName, PANTHEIOS_BE_FILE_F_TRUNCATE,PANTHEIOS_BE_FILE_F_TRUNCATE, PANTHEIOS_BEID_LOCAL); pantheios::log(pantheios::debug, "Entering main"); I get the Init Passed message box but no log statements are dumped in the file.

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  • Understanding Thread/BeginInvoke? [beginner]

    - by Moberg
    Consider the code: class Work { public void DoStuff(string s) { Console.WriteLine(s); // .. whatever } } class Master { private readonly Work work = new Work(); public void Execute() { string hello = "hello"; // (1) is this an ugly hack ? var thread1 = new Thread(new ParameterizedThreadStart(o => this.work.DoStuff((string)o))); thread1.Start(hello); thread1.Join(); // (2) is this similar to the one above? new Action<string>(s => this.work.DoStuff(s)).BeginInvoke(hello, null, null); } } Is (1) an acceptable way of easy starting some work in a seperate thread? If not a better alternative would be much appreciated. Is (2) doing the same? I guess what I ask is if a new thread is started, or.. Hope you can help a beginner to a better understanding :) /Moberg

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  • Error: java.lang.ClassCastException

    - by theJava
    Updating the entire post. public Login authenticate(Login login) { String query = "SELECT email, id FROM Login WHERE email=? AND password=?"; Object[] parameters = { login.getEmail(), login.getPassword() }; List resultsList = getHibernateTemplate().find(query,parameters); if ( resultsList.size() == 1 ) { results = (Login)resultsList.get(0); System.out.println(results); } else { System.out.println("Error dude.... "); // error no entity or mutiple entities } return results; } I now return Login Objects. private void checkLogin() { form.commit(); Login newUser = new Login(); newUser = ilogin.authenticate(loginbean); System.out.println("Its Null Value" + newUser); if (newUser == null) { getWindow().showNotification("Login failed", LOGIN_ERROR_MSG, Notification.TYPE_WARNING_MESSAGE); } else { System.out.println(newUser); getApplication().setUser(newUser); } } When there is no matching email, i get there is no such user and also this statement does get printed out. System.out.println("Its Null Value" + newUser); But when there is a email and password matching. I get weird error. Caused by: java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.intermedix.domain.Login at com.intermedix.services.LoginService.authenticate(LoginService.java:30) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:301) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204) at $Proxy32.authenticate(Unknown Source) at com.intermedix.ui.LoginDailog.checkLogin(LoginDailog.java:106) at com.intermedix.ui.LoginDailog.access$0(LoginDailog.java:102) at com.intermedix.ui.LoginDailog$1.buttonClick(LoginDailog.java:52) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:487) ... 26 more

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  • Serelization of a class and its sub-class....

    - by Amit
    There is a main class having 2 subClasses(each represent separate entity) and all classes needs to be serialized.. how should I proceed ? My requirement is when I serelize MainClass, I should get the xml for each sub class and main class as well. Thanks in advance... and if my approach is incorrect... correct that as well.. Ex given below... class MainClass { SubClass1 objSubclass1 = null; SubClass2 objSubclass2 = null; public MainClass() { objSubclass1 = new SubClass1(); objSubclass2 = new SubClass2(); } [XmlElement("SubClass1")] public SubClass1 SubClass1 {get {return objSubclass1;} } [XmlElement("SubClass2")] public SubClass2 SubClass2 {get {return objSubclass2;} } } Class SubClass1 { Some properties here... } Class SubClass2 { Some properties here... }

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  • How to create stackoverflow's post voting like ajax function?

    - by Daoming Yang
    Can I use Ajax or Jquery to call a action and change the image, just like stackoverflow's post voting function? In my view, I'm using the following code, but I don't want to refresh the browser. Can anyone provide some code about this? <%if (!item.IsPrinted) { %> <%=Html.ImageLink("~/Content/images/web/delete.png", "printed", "MarkAsPrinted", "Order", item.TaskID, null, null)%> <%} else {%> <img src="~/Content/images/web/star.png" alt="printed" /> <% } %>

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  • How to create stackoverflow's post voting like jquery/ajax function?

    - by Daoming Yang
    Can I use Jquery to call an action and then change the image when it success, just like stackoverflow's post voting function? In my view, I'm using the following code, but I don't want to refresh the browser. Can anyone provide some code about this for me? Many thanks. <%if (!item.IsPrinted) { %> <%=Html.ImageLink("~/Content/images/web/delete.png", "printed", "MarkAsPrinted", "Order", item.TaskID, null, null)%> <%} else {%> <img src="~/Content/images/web/star.png" alt="printed" /> <% } %>

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  • Why no switch on pointers?

    - by meeselet
    For instance: #include <stdio.h> void why_cant_we_switch_him(void *ptr) { switch (ptr) { case NULL: printf("NULL!\n"); break; default: printf("%p!\n", ptr); break; } } int main(void) { void *foo = "toast"; why_cant_we_switch_him(foo); return 0; } gcc test.c -o test test.c: In function 'why_cant_we_switch_him': test.c:5: error: switch quantity not an integer test.c:6: error: pointers are not permitted as case values Just curious. Is this a technical limitation? EDIT People seem to think there is only one constant pointer expression. Is that is really true, though? For instance, here is a common paradigm in Objective-C (it is really only C aside from NSString, id and nil, which are merely a pointers, so it is still relevant — I just wanted to point out that there is, in fact, a common use for it, despite this being only a technical question): #include <stdio.h> #include <Foundation/Foundation.h> static NSString * const kMyConstantObject = @"Foo"; void why_cant_we_switch_him(id ptr) { switch (ptr) { case kMyConstantObject: // (Note that we are comparing pointers, not string values.) printf("We found him!\n"); break; case nil: printf("He appears to be nil (or NULL, whichever you prefer).\n"); break; default: printf("%p!\n", ptr); break; } } int main(void) { NSString *foo = @"toast"; why_cant_we_switch_him(foo); foo = kMyConstantObject; why_cant_we_switch_him(foo); return 0; } gcc test.c -o test -framework Foundation test.c: In function 'why_cant_we_switch_him': test.c:5: error: switch quantity not an integer test.c:6: error: pointers are not permitted as case values It appears that the reason is that switch only allows integral values (as the compiler warning said). So I suppose a better question would be to ask why this is the case? (though it is probably too late now.)

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  • Prevent DTD download when parsing XML, redux

    - by harpo
    I have a folder full of XHTML files, and a console program to process them. The problem is, it doesn't work when I'm offline, because The remote name could not be resolved: 'www.w3.org' A number of sites, including this one, say to set the XmlResolver to null. That is not not working. I have tried setting the XmlResolver to null every way that I can think of: in the XmlDocument, in XmlTextReader, and in the XmlReaderSettings. I believe that it's just creating a default instance. I have also tried implementing my own XmlResolver, but I don't know what to return for external items. public class NonXmlResolver : XmlUrlResolver { public override object GetEntity( Uri absoluteUri, string role, Type ofObjectToReturn ) { if ( absoluteUri.Scheme == "http" ) throw new Exception("What you talking 'bout, Willis?"); else return base.GetEntity( absoluteUri, role, ofObjectToReturn ); } } The documents do not use any special entities, only pure XML. This is possible, right?

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  • Why does this crash?

    - by Adam Driscoll
    I've been banging my head...I can't pretend to be a C++ guy... TCHAR * pszUserName = userName.GetBuffer(); SID sid; SecureZeroMemory(&sid, sizeof(sid)); SID_NAME_USE sidNameUse; DWORD cbSid = sizeof(sid); pLog->Log(_T("Getting the SID for user [%s]"), 1, userName); if (!LookupAccountName(NULL, (LPSTR)pszUserName, &sid, &cbSid, NULL, 0, &sidNameUse)) { pLog->Log(_T("Failed to look up user SID. Error code: %d"),1, GetLastError()); return _T(""); } pLog->Log(_T("Converting binary SID to string SID")); The message 'Getting the SID for user [x] is written' but then the app crashes. I'm assuming is was the LookupAccountName call. EDIT: Whoops userName is a MFC CString

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  • Photoshop, slice, Dreamweaver, web?

    - by Omega
    So I am playing around with Photoshop and Dreamweaver. I have created a site layout, and have used the slice function on it. Next, I saved as html & images. In Dreamweaver, I open such html file and I fill the page with content, links, etc. I have a website and everything, and I would like to use my newly created html page on it. But, obviously, if I copy & paste the html to my website it won't work because it will lack the images. But two things: I can't find the images, and apparently they are a lot. I am sure I am doing a great mistake regarding the images. Can someone help me?

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  • ASP.NET MVC: Posting JSON to Controller

    - by JamesBrownIsDead
    I've got this in my controller: [HttpPost] public void UpdateLanguagePreference(string languageTag) { if (string.IsNullOrEmpty(languageTag)) { throw new ArgumentNullException("languageTag"); } ... } And have this jQuery code POSTing to the controller: jQuery.ajax({ type: 'POST', url: '/Config/UpdateLanguagePreference', contentType: 'application/json; charset=utf-8', data: '{ "languageTag": "' + selectedLanguage + '" }' }); When I try to the code, however, I get the error: Server Error in '/' Application. Value cannot be null. Parameter name: languageTag What's the problem? Isn't this how to POST JSON to an MVC Controller? I can examine the POST using Fiddler and see that the request is correct. For some reason, UpdateLanguagePreference() is getting a null or empty string.

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  • mysql GROUP_CONCAT

    - by user301766
    I want to list all users with their corropsonding user class. Here are simplified versions of my tables CREATE TABLE users ( user_id INT NOT NULL AUTO_INCREMENT, user_class VARCHAR(100), PRIMARY KEY (user_id) ); INSERT INTO users VALUES (1, '1'), (2, '2'), (3, '1,2'); CREATE TABLE classes ( class_id INT NOT NULL AUTO_INCREMENT, class_name VARCHAR(100), PRIMARY KEY (class_id) ); INSERT INTO classes VALUES (1, 'Class 1'), (2, 'Class 2'); And this is the query statement I am trying to use but is only returning the first matching user class and not a concatenated list as hoped. SELECT user_id, GROUP_CONCAT(DISTINCT class_name SEPARATOR ",") AS class_name FROM users, classes WHERE user_class IN (class_id) GROUP BY user_id; Actual Output +---------+------------+ | user_id | class_name | +---------+------------+ | 1 | Class 1 | | 2 | Class 2 | | 3 | Class 1 | +---------+------------+ Wanted Output +---------+---------------------+ | user_id | class_name | +---------+---------------------+ | 1 | Class 1 | | 2 | Class 2 | | 3 | Class 1, Class 2 | +---------+---------------------+ Thanks in advance

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  • lexical analysis gives only one output?

    - by Caffè
    I tested this example(lexe.java), but it gave me only one output. I gave this text as a reader: public class LexeTest{ private int a = 14; } And the nextToken() function is : public Category nextToken () { if (inp.findWithinHorizon (tokenPat, 0) == null) return Category.EOF; else { lastLexeme = inp.match ().group (0); if (inp.match ().start (1) != -1) return nextToken (); else if (inp.match ().start (2) != -1) return Category.IDENT; else if (inp.match ().start (3) != -1) return Category.NUMERAL; Category result = tokenMap.get (lastLexeme); if (result == null) return Category.ERROR; else return result; } } Isdie the main method: System.out.println(lexeObject.nextToken()); output is : IDENT Why? but the textfile contains multiple keywords? Anyone know what's the problem?

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  • Query joining in sql server 2005

    - by Domnic
    I have two queries like: SELECT PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO ACCOUNT, COUNT(PC_CHEQUE_NO) CHQS, SUM(CONVERT(FLOAT, PC_AMOUNT)) CHQ_AMT FROM GLAS_PDC_CHEQUES WHERE PC_COMP_CODE = '1' AND PC_DISCD IS NULL GROUP BY PC_SL_LDGR_CODE, PC_SL_ACNO ,PC_COMP_CODE ORDER BY PC_SL_ACNO -------------------------------------------------- SELECT COAD_PTY_FULL_NAME,PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO, PC_DEPT_NO, PC_DOC_TYPE, PC_CHEQUE_NO, PC_BANK_AC_NO FROM GLAS_PTY_ADDRESS,GLAS_SBLGR_MASTERS,GLAS_PDC_CHEQUES WHERE COAD_COMP_CODE = '1' AND SLMA_COMP_CODE = COAD_COMP_CODE AND SLMA_ADDR_ID = COAD_ADDR_ID AND SLMA_LDGRCTL_CODE = PC_SL_LDGR_CODE AND PC_COMP_CODE=SLMA_COMP_CODE AND SLMA_ACNO = PC_SL_ACNO AND SLMA_LDGRCTL_YEAR = DBO.GLAS_VALIDATIONS_GET_OPEN_YEAR(PC_COMP_CODE) If I execute first query alone I get 5 records... If I join the above two query like: SELECT PC_COMP_CODE, PC_SL_LDGR_CODE, PC_SL_ACNO ACCOUNT, COUNT(PC_CHEQUE_NO) CHQS, SUM(CONVERT(FLOAT, PC_AMOUNT)) CHQ_AMT, COAD_PTY_FULL_NAME FROM GLAS_PDC_CHEQUES LEFT OUTER JOIN GLAS_SBLGR_MASTERS ON( SLMA_COMP_CODE=PC_COMP_CODE AND SLMA_LDGRCTL_CODE = PC_SL_LDGR_CODE AND SLMA_ACNO = PC_SL_ACNO ) LEFT OUTER JOIN GLAS_PTY_ADDRESS ON( SLMA_COMP_CODE = COAD_COMP_CODE AND SLMA_ADDR_ID = COAD_ADDR_ID) WHERE PC_COMP_CODE = '1' AND PC_DISCD IS NULL AND SLMA_LDGRCTL_YEAR = DBO.GLAS_VALIDATIONS_GET_OPEN_YEAR(PC_COMP_CODE) GROUP BY PC_SL_LDGR_CODE, PC_SL_ACNO ,PC_COMP_CODE,COAD_PTY_FULL_NAME ORDER BY PC_SL_ACNO then I just get 2 records.... I need that 5 records to display after join..... How can I do it?

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  • best practice on precedence of variable declaration and error handling in C

    - by guest
    is there an advantage in one of the following two approaches over the other? here it is first tested, whether fopen succeeds at all and then all the variable declarations take place, to ensure they are not carried out, since they mustn't have had to void func(void) { FILE *fd; if ((fd = fopen("blafoo", "+r")) == NULL ) { fprintf(stderr, "fopen() failed\n"); exit(EXIT_FAILURE); } int a, b, c; float d, e, f; /* variable declarations */ /* remaining code */ } this is just the opposite. all variable declarations take place, even if fopen fails void func(void) { FILE *fd; int a, b, c; float d, e, f; /* variable declarations */ if ((fd = fopen("blafoo", "+r")) == NULL ) { fprintf(stderr, "fopen() failed\n"); exit(EXIT_FAILURE); } /* remaining code */ } does the second approach produce any additional cost, when fopen fails? would love to hear your thoughts!

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  • JSR-303 dependency injection and Hibernate

    - by Jam
    Spring 3.0.2, Hibernate 3.5.0, Hibernate-Validator 4.0.2.GA I am trying to inject Spring dependencies into a ConstraintValidator using: @PersistenceContext private EntityManager entityManager; I have configured the application context with: <bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean"/> Which, according to the Spring documentation, should allow “custom ConstraintValidators to benefit from dependency injection like any other Spring bean” Within the debugger I can see Spring calling getBean to create the ConstraintValidator. Later when flush triggers the preInsert, a different ConstraintValidator is created and called. The problem is the EntityManager is null within this new ConstraintValidator. I’ve tried injecting other dependencies within the ConstraintValidator and these are always null. Does anyone know if it is possible to inject dependencies into a ConstraintValidator?

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  • How to encrypt and save a binary stream after serialization and read it back?

    - by Anindya Chatterjee
    I am having some problems in using CryptoStream when I want to encrypt a binary stream after binary serialization and save it to a file. I am getting the following exception System.ArgumentException : Stream was not readable. Can anybody please show me how to encrypt a binary stream and save it to a file and deserialize it back correctly? The code is as follows: class Program { public static void Main(string[] args) { var b = new B {Name = "BB"}; WriteFile<B>(@"C:\test.bin", b, true); var bb = ReadFile<B>(@"C:\test.bin", true); Console.WriteLine(b.Name == bb.Name); Console.ReadLine(); } public static T ReadFile<T>(string file, bool decrypt) { T bObj = default(T); var _binaryFormatter = new BinaryFormatter(); Stream buffer = null; using (var stream = new FileStream(file, FileMode.OpenOrCreate)) { if(decrypt) { const string strEncrypt = "*#4$%^.++q~!cfr0(_!#$@$!&#&#*&@(7cy9rn8r265&$@&*E^184t44tq2cr9o3r6329"; byte[] dv = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}; CryptoStream cs; DESCryptoServiceProvider des = null; var byKey = Encoding.UTF8.GetBytes(strEncrypt.Substring(0, 8)); using (des = new DESCryptoServiceProvider()) { cs = new CryptoStream(stream, des.CreateEncryptor(byKey, dv), CryptoStreamMode.Read); } buffer = cs; } else buffer = stream; try { bObj = (T) _binaryFormatter.Deserialize(buffer); } catch(SerializationException ex) { Console.WriteLine(ex.Message); } } return bObj; } public static void WriteFile<T>(string file, T bObj, bool encrypt) { var _binaryFormatter = new BinaryFormatter(); Stream buffer; using (var stream = new FileStream(file, FileMode.Create)) { try { if(encrypt) { const string strEncrypt = "*#4$%^.++q~!cfr0(_!#$@$!&#&#*&@(7cy9rn8r265&$@&*E^184t44tq2cr9o3r6329"; byte[] dv = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF}; CryptoStream cs; DESCryptoServiceProvider des = null; var byKey = Encoding.UTF8.GetBytes(strEncrypt.Substring(0, 8)); using (des = new DESCryptoServiceProvider()) { cs = new CryptoStream(stream, des.CreateEncryptor(byKey, dv), CryptoStreamMode.Write); buffer = cs; } } else buffer = stream; _binaryFormatter.Serialize(buffer, bObj); buffer.Flush(); } catch(SerializationException ex) { Console.WriteLine(ex.Message); } } } } [Serializable] public class B { public string Name {get; set;} } It throws the serialization exception as follows The input stream is not a valid binary format. The starting contents (in bytes) are: 3F-17-2E-20-80-56-A3-2A-46-63-22-C4-49-56-22-B4-DA ...

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  • Issue using Session in MVC Actions with [authorice]

    - by Pablo Gonzalez
    Hi all, first of all sorry for my poor English! When I use the [Authorice` attribute i can't get Session data that i stored before. For example: public ViewResult Index() { // do some stuffs Session["Test"] = "Hi stackoverflow!"; } And then i try to get it in another action, but with the [Authorize] attibute [Authorize] public ViewResult Test() { // do some stuffs if(Session["Test"] == null) { //do some stuffs } } Session["Test"] is always null, but if i remove the attribute it's work, may anyone help me?, thanks a lot!!! P.S: I instance Session["Test"] in Session_Start

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  • Why is NavigationHandler.handleNavigation() not forwarding to view ID?

    - by Erik Hermansen
    Inside of a phase listener class that runs during the "RESTORE_VIEW" phase, I have some code like this: public void afterPhase(PhaseEvent event) { FacesContext fc = event.getFacesContext(); NavigationHandler nh = fc.getApplication().getNavigationHandler(); nh.handleNavigation(fc, null, "/a/specific/path/to/a/resource.jspx"); } Navigation to the new URL doesn't work here. The request made will just receive a response from the original JSPX that was navigated to. Code like this works fine: public void afterPhase(PhaseEvent event) { FacesContext fc = event.getFacesContext(); NavigationHandler nh = fc.getApplication().getNavigationHandler(); nh.handleNavigation(fc, null, "OUTCOME_DEFINED_IN_FACES_CONFIG_XML"); } Also the first snippet will work with an IceFaces Faces provider, but not Sun JSF 1.2 which is what I need to use. Is there something I can do to fix the code so it is possible to forward to specific URLs?

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  • Get data types from arbitrary sql statement in SQL Server 2008

    - by Christopherous 5000
    Given some arbitrary SQL I would like to get the data types of the returned columns. The statement might join many tables, views, TVFs, etc. I know I could create a view based on the query and get the datatypes from that, hoping there's a quicker way. Only think I've been able to think of is writing a .net utility to run the SQL and examine the results, wondering if there is a TSQL answer. i.e. Given (not real tables just an example) SELECT p.Name AS PersonName, p.Age, a.Account as AccountName FROM Person as p LEFT JOIN Account as a ON p.Id = a.OwnerId I would like to have something like PersonName: (nvarchar(255), not null) Age: (smallInt, not null) etc...

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  • NSBitmapImageRep data Format as application icon image??

    - by Joe
    i have a char* array of data that was in RGBA and then moved to ARGB Bottom line is the set application image looks totally messed up and i cant put my finger on why? //create a bitmap representation of the image data. //The data is expected to be unsigned char** NSBitmapImageRep *bitmap = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes : (unsigned char**) &dest pixelsWide:width pixelsHigh:height bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSDeviceRGBColorSpace bitmapFormat:NSAlphaFirstBitmapFormat bytesPerRow: 0 bitsPerPixel:0 ]; NSImage *image = [[NSImage alloc] initWithSize:NSMakeSize(width, height)]; [image addRepresentation:bitmap]; if( image == NULL) { printf("image is null\n"); fflush(stdout); } [NSApp setApplicationIconImage :image]; What in these values is off? the image looks very multicolored and pixelated, with transparent parts/lines as well.

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  • How do I detect a loop in this linked list?

    - by jjujuma
    Say you have a linked list structure in Java. It's made up of Nodes: class Node { Node next; // some user data } and each Node points to the next node, except for the last Node, which has null for next. Say there is a possibility that the list can contain a loop - i.e. the final Node, instead of having a null, has a reference to one of the nodes in the list which came before it. What's the best way of writing boolean hasLoop(Node first) which would return true if the given Node is the first of a list with a loop, and false otherwise? How could you write so that it takes a finite amount of space and a reasonable amount of time?

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  • ADO.NET: Faster way to check if the database server is accessible?

    - by lotana
    At the moment I am using this code to check if the database is accessible: public bool IsDatabaseOnline(string con) { bool isConnected = false; SQLConnection connect = null; try { connect = new SQLConnection(con); connect.Open(); isConnected = true; } catch (Exception e) { isConnected = false; } finally { if (connect != null) connect.Close(); } return isConnected; } While this code works fine, there is a disadvantage. If the server is not online it spends about 4 full seconds trying to open the connection before deciding that it is not available. Is there a way to test the connection without trying to actually opening it and waiting for the timeout? Something like a database-equivalent of ping?

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  • How-to dispose a waithandle correctly

    - by TomTom
    Hello, I'm doing some multi-threading and use AutoResetEvents and ManualResetEvents do control my main - loop. When "destryoing" the threads I also have to dispose these signals, that's clear. But I saw different ways how to dispose Waithandles, and I'm not sure which one is correct: Version 1 if (disposing) { this.threadExitEvent.SafeWaitHandle.Dispose(); this.threadExitEvent.Close(); this.threadExitEvent = null; .... } Version 2 if (disposing) { this.threadExitEvent.Close(); this.threadExitEvent = null; .... } Version 3 if (disposing) { this.threadExitEvent.Close(); .... }

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