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  • How to know the type of an object in a list?

    - by nacho4d
    Hi, I want to know the type of object (or type) I have in my list so I wrote this: void **list; //list of references list = new void * [2]; Foo foo = Foo(); const char *not_table [] = {"tf", "ft", 0 }; list[0] = &foo; list[1] = not_table; if (dynamic_cast<LogicProcessor*>(list[0])) { //ERROR here ;( printf("Foo was found\n"); } if (dynamic_cast<char*> (list[0])) { //ERROR here ;( printf("char was found\n"); } but I get : error: cannot dynamic_cast '* list' (of type 'void*') to type 'class Foo*' (source is not a pointer to class) error: cannot dynamic_cast '* list' (of type 'void*') to type 'char*' (target is not pointer or reference to class) Why is this? what I am doing wrong here? Is dynamic_cast what I should use here? Thanks in advance EDIT: I know above code is much like plain C and surely sucks from the C++ point of view but is just I have the following situation and I was trying something before really implementing it: I have two arrays of length n but both arrays will never have an object at the same index. Hence, or I have array1[i]!=NULL or array2[i]!=NULL. This is obviously a waste of memory so I thought everything would be solved if I could have both kind of objects in a single array of length n. I am looking something like Cocoa's (Objective-C) NSArray where you don't care about the type of the object to be put in. Not knowing the type of the object is not a problem since you can use other method to get the class of a certain later. Is there something like it in c++ (preferably not third party C++ libraries) ? Thanks in advance ;)

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  • C# XML Documentation Compiler Warning

    - by ImperialLion
    I am curious as to why I get a compiler warning in the following situation. /// <summary>This is class A /// </summary> public class A { /// <summary>This is the documentation for Method A /// </summary> public void MethodA() { //Do something } } /// <summary>This is class B /// </summary> public class B : A { /// <summary>This does something that I want to /// reference <see cref="MethodA"/> /// </summary> public void MethodB() { //Do something } } The warning states that "XML comment on 'B.MethodB()' has cref attribute 'MethodA' that could not be resolved." If B inherits from A shouldn't the compiler be able to see that method when generating the documentation without me specifying the parent class in the cref? If I change the cref to be cref="A.MethodA()" it works fine, but it seems like that's unnecessary and is a pain to do, especially if I have to go up more than one level. As a note to anyone testing this you have to be sure to "XML documentation file" checked in the Properties - Build in order to see the warning.

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  • how to organize classes in ruby if they are literal subclasses

    - by RetroNoodle
    I know that title didn't make sense, Im sorry! Its hard to word what I am trying to ask. I had trouble googling it for the same reason. So this isn't even Ruby specific, but I am working in ruby and I am new to it, so bear with me. So you have a class that is a document. Inside each document, you have sentences, and each sentence has words. Words will have properties, like "noun" or a count of how many times they are used in the document, etc. I would like each of the elements, document, sentence, word be an object. Now, if you think literally - sentences are in documents, and words are in sentences. Should this be organized literally like this as well? Like inside the document class you will define and instantiate the sentence objects, and inside the sentence class you will define and instantiate the words? Or, should everything be separate and reference each other? Like the word class would sit outside the sentence class but the sentence class would be able to instantiate and work with words? This is a basic OOP question I guess, and I suppose you could argue to do it either way. What do you guys think? Each sentence in the document could be stored in a hash of sentence objects inside the document object, and each word in the sentence could be stored in a hash of word objects inside the sentence. I dont want to code myself into a corner here, thats why I am asking, plus I have wondered this before in other situations. Thank you!

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  • retrieve only sub-pages (wordpress)

    - by Radek
    I want to list all sub-pages only one level though of one particular page. I was reading Function Reference/get pages and thought that $pages = get_pages( array( 'child_of' => $post->ID, 'parent' => $post->ID)) ; will do the trick but it is not working. It lists all pages on the same level like the page I call that code from. If I omit parent option I will get all pages even with sub-pages that I want. But I want only sub-pages. The whole function is like function about_menu(){ if (is_page('about')){ $pages = get_pages( array( 'child_of' => $post->ID, 'parent' => $post->ID)) ; foreach($pages as $page) { ?> <h2><a href="<?php echo get_page_link($page->ID) ?>"><?php echo $page->post_title ?></a></h2> <?php } } } and mine is second one

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  • creating a vector with references to some of the elements of another vector

    - by memC
    hi, I have stored instances of class A in a std:vector, vec_A as vec_A.push_back(A(i)). The code is shown below. Now, I want to store references some of the instances of class A (in vec_A) in another vector or another array. For example, if the A.getNumber() returns 4, 7, 2 , I want to put a reference to that instance of A in another vector, say std:vector<A*> filtered_A or an array. Can someone sow me how to do this?? Thanks! class A { public: int getNumber(); A(int val); ~A(){}; private: int num; }; A::A(int val){ num = val; }; int A::getNumber(){ return num; }; int main(){ int i =0; int num; std::vector<A> vec_A; for ( i = 0; i < 10; i++){ vec_A.push_back(A(i)); } std::cout << "\nPress RETURN to continue..."; std::cin.get(); return 0; }

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  • help with basic MVC project

    - by Shrewd Demon
    hi, i am creating a demo MVC project and i am getting a Null Object Reference error for the following code. <% foreach (var item in Model) { %> <tr> <td> <%= Html.ActionLink("Edit", "Edit", new { /* id=item.PrimaryKey */ }) %> | <%= Html.ActionLink("Details", "Details", new { /* id=item.PrimaryKey */ })%> | <%= Html.ActionLink("Delete", "Delete", new { /* id=item.PrimaryKey */ })%> </td> <td> <%= Html.Encode(item.ContactEmail) %> </td> <td> <%= Html.Encode(item.YourQuery) %> </td> </tr> <% } %> i get an error in the first line itself (var item in Model) coz i am getting the Model object as null. Can anyone please help me. thanks.

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  • What rules govern the copying of variables in Javascript closures?

    - by int3
    I'd just like to check my understanding of variable copying in Javascript. From what I gather, variables are passed/assigned by reference unless you explicitly tell them to create a copy with the new operator. But I'm a little uncertain when it comes to using closures. Say I have the following code: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; console.log(x); }); } fnlist[2](); // returns 20 I gather that this is because fnlist[2] only looks up the value of data at the point where it is invoked. So I tried an alternative tack: var myArray = [1, 5, 10, 15, 20]; var fnlist = []; for (var i in myArray) { var data = myArray[i]; fnlist.push(function() { var x = data; return function() { console.log(x); } }()); } fnlist[2](); // returns 10 So now it returns the 'correct' value. Am I right to say that it works because a function resolves all variable references to their 'constant' values when it is invoked? Or is there a better way to explain it? Any explanations / links to explanations regarding this referencing / copying business would be appreciated as well. Thanks!

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  • Javascript object properties access functions in parent constructor?

    - by Bob Spryn
    So I'm using this pretty standard jquery plugin pattern whereby you can grab an api after applying the jquery function to a specific instance. This API is essentially a javascript object with a bunch of methods and data. So I wanted to essentially create some private internal methods for the object only to manipulate data etc, which just doesn't need to be available as part of the API. So I tried this: // API returned with new $.TranslationUI(options, container) $.TranslationUI = function (options, container) { // private function? function monkey(){ console.log("blah blah blah"); } // extend the default settings with the options object passed this.settings = $.extend({},$.TranslationUI.defaultSettings,options); // set a reference for the container dom element this.container = container; // call the init function this.init(); }; The problem I'm running into is that init can't call that function "monkey". I'm not understanding the explanation behind why it can't. Is it because init is a prototype method?($.TranslationUI's prototype is extended with a bunch of methods including init elsewhere in the code) $.extend($.TranslationUI, { prototype: { init : function(){ // doesn't work monkey(); // editing flag this.editing = false; // init event delegates here for // languagepicker $(this.settings.languageSelector, this.container).bind("click", {self: this}, this.selectLanguage); } } }); Any explanations would be helpful. Would love other thoughts on creating private methods with this model too. These particular functions don't HAVE to be in prototype, and I don't NEED private methods protected from being used externally, but I want to know how should I have that requirement in the future.

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  • .NET memory leak?

    - by SA
    I have an MDI which has a child form. The child form has a DataGridView in it. I load huge amount of data in the datagrid view. When I close the child form the disposing method is called in which I dispose the datagridview this.dataGrid.Dispose(); this.dataGrid = null; When I close the form the memory doesn't go down. I use the .NET memory profiler to track the memory usage. I see that the memory usage goes high when I initially load the data grid (as expected) and then becomes constant when the loading is complete. When I close the form it still remains constant. However when I take a snapshot of the memory using the memory profiler, it goes down to what it was before loading the file. Taking memory snapshot causes it to forcefully run garbage collector. What is going on? Is there a memory leak? Or do I need to run the garbage collector forcefully? More information: When I am closing the form I no longer need the information. That is why I am not holding a reference to the data.

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  • How do I repeat function over several row.

    - by ChrisBD
    I'll admit that I'm not an Excel guru so maybe someone here can help me. On my worksheet I have several blocks of data. I calculate the sum of all items within column D of that block. Within each block I am checking the value of the cell in column C and if it contains the letter "y" and the value in column D of that row is equal to zero I must exclude the total sum of column D. Currently I am doing this by multiplying the sum value by either 1 or 0 which is produced by running a test over the cell contents. Below is an example of what I am using to test rows 23 to row 25 inclusively for data in Column D. I am also performing the same on Column E and G, but the "y" character is always in column C, hence the absolut column reference. =IF(AND($C23="y",D23=0),0,1)*IF(AND($C24="y",D24=0),0,1)*IF(AND($C25="y",D25=0),0,1) There must be a more efficient way to do this. Ideally I would like to write a function that I can paste into a cell and then select the rows or cells over which I run the test. Can anyone point me in the right direction?

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  • Java - How to pass a Generic parameter as Class<T> to a constructor

    - by Joe Almore
    I have a problem here that still cannot solve, the thing is I have this abstract class: public abstract class AbstractBean<T> { private Class<T> entityClass; public AbstractBean(Class<T> entityClass) { this.entityClass = entityClass; }... Now I have another class that inherits this abstract: @Stateless @LocalBean public class BasicUserBean<T extends BasicUser> extends AbstractBean<T> { private Class<T> user; public BasicUserBean() { super(user); // Error: cannot reference user before supertype contructor has been called. } My question is how can I make this to work?, I am trying to make the class BasicUserBean inheritable, so if I have class PersonBean which inherits BasicUserBean then I could set in the Generic the entity Person which also inherits the entity BasicUser. And it will end up being: @Stateless @LocalBean public class PersonBean extends BasicUserBean<Person> { public PersonBean() { super(Person.class); } ... I just want to inherit the basic functionality from BasicUserBean to all descendants, so I do not have to repeat the same code among all descendants. Thanks!.

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  • Generic Singleton Fasade design pattern

    - by Paul
    Hi I try write singleton fasede pattern with generics. I have one problem, how can I call method from generic variable. Something like this: T1 t1 = new T1(); //call method from t1 t1.Method(); In method SingletonFasadeMethod I have compile error: Error 1 'T1' does not contain a definition for 'Method' and no extension method 'Method' accepting a first argument of type 'T1' could be found (are you missing a using directive or an assembly reference?) Any advace? Thank, I am beginner in C#. All code is here: namespace GenericSingletonFasade { public interface IMyInterface { string Method(); } internal class ClassA : IMyInterface { public string Method() { return " Calling MethodA "; } } internal class ClassB : IMyInterface { public string Method() { return " Calling MethodB "; } } internal class ClassC : IMyInterface { public string Method() { return "Calling MethodC"; } } internal class ClassD : IMyInterface { public string Method() { return "Calling MethodD"; } } public class SingletonFasade<T1,T2,T3> where T1 : class,new() where T2 : class,new() where T3 : class,new() { private static T1 t1; private static T2 t2; private static T3 t3; private SingletonFasade() { t1 = new T1(); t2 = new T2(); t3 = new T3(); } class SingletonCreator { static SingletonCreator() { } internal static readonly SingletonFasade<T1,T2,T3> uniqueInstace = new SingletonFasade<T1,T2,T3>(); } public static SingletonFasade<T1,T2,T3> UniqueInstace { get { return SingletonCreator.uniqueInstace; } } public string SingletonFasadeMethod() { //Problem is here return t1.Method() + t2.Method() + t3.Method(); } } }

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  • Get element id on hover (or mouseover)

    - by Peter C
    Still getting to grips with jQuery and I am pleased to have got as far as I have, especially help from the posts in this forum. However, now got to a working function that does what I want, that is to create a radio group that looks like a button. It pulls data via json and loops through creating the radio buttons. I want to get the id of the radio buttons generated so that I can then parse through to the next step of the app but I can't get it to work. function FillDiv(groups, side) { var cnt = 1; var newClass = ''; var newType = ''; if (side == '#ck-button-left') { newClass = 'leftClass'; newType = 'radio' } else { newClass = 'rightClass'; newType = 'checkbox' } $.each(groups, function (index, groups) { $(side) .append( $(document.createElement('label')).attr({ id: cnt + 'lbl' }) ); $('#' + cnt + 'lbl') .append( $(document.createElement('input')).attr({ id: groups.GroupCode, type: newType, name: 'testGroup', class: newClass }) ); $('#' + groups.GroupCode).after ( $(document.createElement('span')).text(groups.GroupName).attr('class', 'leftSpan') ); $('#' + cnt + 'lbl').after($(document.createElement('br'))); cnt = cnt + 1; }); } Looking through various searched, it should work with something like... $('#leftSpan').mouseover(function () { $('#lblOutput').html(this.id); }); or, as I suspect, it is something to do with the nesting of the label/input that I need to reference the parent or child. Any pointers would be appreciated.

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  • Exposing a C++ API to C#

    - by Siyfion
    So what I have is a C++ API contained within a *.dll and I want to use a C# application to call methods within the API. So far I have created a C++ / CLR project that includes the native C++ API and managed to create a "bridge" class that looks a bit like the following: ManagedBridge.h namespace ManagedAPIWrapper { public ref class Bridge { public: int bridge_test(void); int bridge_test2(api_struct* temp); } } ManagedBridge.cpp int Bridge::bridge_test(void) { return test(); } int Bridge::bridge_test2(api_struct* temp) { return test2(temp); } I also have a C# application that has a reference to the C++/CLR "Bridge.dll" and then uses the methods contained within. I have a number of problems with this: I can't figure out how to call bridge_test2 within the C# program, as it has no knowledge of what a api_struct actually is. I know that I need to marshal the object somewhere, but do I do it in the C# program or the C++/CLR bridge? This seems like a very long-winded way of exposing all of the methods in the API, is there not an easier way that I'm missing out? (That doesn't use P/Invoke!)

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  • Split a string by comma, quote and full-stop.. with a few exceptions

    - by dunc
    I've got a lot of text, similar to the following paragraph, which I'd like to split into words without punctuation (', ", ,, ., newline etc).. with a few exceptions. Initially considered endemic to the Chalakudy River system in Kerala state, southern India, but now recognised to have a wider distribution in surrounding drainages including the Periyar, Manimala, and Pamba river though the Manimala data may be questionable given it seems to be the type locality of P. denisonii. In the Achankovil River basin it occurs sympatrically, and sometimes syntopically, with P. denisonii. Wild stocks may have dwindled by as much as 50% in the last 15 years or so with collection for the aquarium trade largely held responsible although habitats are also being degraded by pollution from agricultural and domestic sources, plus destructive fishing methods involving explosives or organic toxins. The text refers to P. denisonii which is a species of fish. It's an abbreviation of Genus species. I would like this reference to be one word. So, for instance, this is the kind of array I'd like to see: Array ( ... [44] given [45] it [46] seems [47] to [48] be [49] the [50] type [51] locality [52] of [53] P. denisonii [54] In [55] the ... ) The only things that distinguish these species references such as P. denisonii from a new sentence like end. New are: The P (for Puntius, as in the P. in the aforementioned example) is only ever one letter, always a capital the d (as in . denisonii) is always either a lower case letter or an apostrophe (') What regexp can I use with preg_split to give me such an array? I've tried a simple explode( " ", $array ) but it doesn't do the job at all. Thanks in advance,

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  • Error emailing outgoing sms

    - by BirthOfTragedy
    Is there anyway to listen for an outbound sms without having to import javax.wireless.messaging? I'm trying to write an app that listens for an sms sent from the device then emails the message of the sms, but I get the error: reference to Message is ambiguous, both class javax.wireless.messaging.Message in javax.wireless.messaging and class net.rim.blackberry.api.mail.Message in net.rim.blackberry.api.mail match I need to import net.rim.blackberry.api.mail.Message in order to sent an email. Is there a way to get around this as it seems that the two packages are clashing. My code: public void notifyIncomingMessage(MessageConnection messageconnection) {} public void notifyOutgoingMessage(javax.wireless.messaging.Message message) { try { String address = message.getAddress(); String msg = null; if ( message instanceof TextMessage ) { TextMessage tm = (TextMessage)message; msg = tm.getPayloadText(); } else if (message instanceof BinaryMessage) { StringBuffer buf = new StringBuffer(); byte[] data = ((BinaryMessage) message).getPayloadData(); msg = new String(data, "UTF-8"); Store store = Session.getDefaultInstance().getStore(); Folder[] folders = store.list(Folder.SENT); Folder sentfolder = folders[0]; Message in = new Message(sentfolder); Address recipients[] = new Address[1]; recipients[0]= new Address("[email protected]", "user"); in.addRecipients(Message.RecipientType.TO, recipients); in.setSubject("Outgoing sms"); in.setContent("You have just sent an sms to: " + address + "\n" + "Message: " + msg); in.setPriority(Message.Priority.HIGH); Transport.send(in); in.setFlag(Message.Flag.OPENED, true); Folder folder = in.getFolder(); folder.deleteMessage(in); } } catch (IOException me) { System.out.println(me); } } }

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  • Java How to find a value in a linked list iteratively and recursively

    - by Roxy
    Hi I have a method that has a reference to a linked list and a int value. So, this method would count and return how often the value happens in the linked list. So, I decided to make a class, public class ListNode{ public ListNode (int v, ListNode n) {value = v; next = n;) public int value; public ListNode next; } Then, the method would start with a public static int findValue(ListNode x, int valueToCount){ // so would I do it like this?? I don't know how to find the value, // like do I check it? for (int i =0; i< x.length ;i++){ valueToCount += valueToCount; } So, I CHANGED this part, If I did this recursively, then I would have public static int findValue(ListNode x, int valueToCount) { if (x.next != null && x.value == valueToCount { return 1 + findValue(x, valueToCount);} else return new findvalue(x, valueToCount); SO, is the recursive part correct now?

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  • Using unions to simplify casts

    - by Steven Lu
    I realize that what I am trying to do isn't safe. But I am just doing some testing and image processing so my focus here is on speed. Right now this code gives me the corresponding bytes for a 32-bit pixel value type. struct Pixel { unsigned char b,g,r,a; }; I wanted to check if I have a pixel that is under a certain value (e.g. r, g, b <= 0x10). I figured I wanted to just conditional-test the bit-and of the bits of the pixel with 0x00E0E0E0 (I could have wrong endianness here) to get the dark pixels. Rather than using this ugly mess (*((uint32_t*)&pixel)) to get the 32-bit unsigned int value, i figured there should be a way for me to set it up so I can just use pixel.i, while keeping the ability to reference the green byte using pixel.g. Can I do this? This won't work: struct Pixel { unsigned char b,g,r,a; }; union Pixel_u { Pixel p; uint32_t bits; }; I would need to edit my existing code to say pixel.p.g to get the green color byte. Same happens if I do this: union Pixel { unsigned char c[4]; uint32_t bits; }; This would work too but I still need to change everything to index into c, which is a bit ugly but I can make it work with a macro if i really needed to.

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  • AS3 colorTransform over multiple frames?

    - by user359519
    (Flash Professional, AS3) I'm working on a custom avatar system where you can select various festures and colors. For example, I have 10 hairstyles, and a colorPicker to change the color. mc_myAvatar has 10 frames. Each frame has a movieclip of a different hairstyle (HairStyle1, HairStyle2, etc.) Here's my code: var hairColor:ColorTransform; hairColor = mc_myAvatar.hair.colorLayer.transform.colorTransform; hairColor.color = 0xCCCC00; mc_myAvatar.hair.colorLayer.transform.colorTransform = hairColor; This correctly changes the initial color. I have a "nextHair" button to advance mc_myAvatar.hair to the next frame. When I click the button, I get an error message saying that I have a null object reference. I added a trace, and mc_myAvatar.hair.colorLayer is null on frame 2. Why??? I've clearly named HairStyle2 as "colorLayer" in frame 2. I think the problem is related to me using the same name for different classes/movieclips, but I don't know how to fix the problem... I added a square movieclip below my hairStyle movieclips, named the square "colorLevel", and deleted the name from my hairStyle clips. When I click the next button, the square correctly maintains the color from frame to frame. However, having a square doesn't do me much good. :( I tried converting the hairStyle layer to a mask. Doing this, however, results in yet another "null object" error - mc_myAvatar.hair.colorLayer is null after frame 1. I even tried "spanning" my colorLevel across all frames (no keyframes), thinking that this would give me just one movieclip to work with. No luck. Same error! What's going on, here? Why am I getting these null objects, when they are clearly defined in my movieclip? I'm also open to suggestions on a better way to do multiple frames and colors.

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  • jQuery .ready() automatically assigning variables for each element with ID in DOM

    - by Greg
    I have noticed some unexpected behaviour when using the jQuery .ready() function, whereby afterwards you can reference an element in the DOM simply by using its ID without prior declaration or assignment: <html> <script src="jquery.js"></script> <script> $(document).ready(function() { myowndiv.innerHTML = 'wow!' }); </script> <body> <div id="myowndiv"></div> </body> </html> I would have expected to have to declare and assign myowndiv with document.getElementById("myowndiv"); or $("#myowndiv"); before I could call innerHTML or anything else on it? Is this behaviour by design? Can anyone explain why? My fear is that if I refactor and end up not using .ready() or even using jQuery at all then my code will fail to execute. Cheers!

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  • Get textboxes in to a list! c#

    - by Chelsea_cole
    public class Account { public string Username { get { return Username; } set { Username = value; } } } public class ListAcc { static void Data() { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; //error UserList.Add(acc); } } there are a error from access to textBox1.Text? ( An object reference is required for the nonstatic field, method, or property)... Someone can help? but if the code is: private void textBox1_TextChanged(object sender, EventArgs e) { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; UserList.Add(acc); } it's work! someone can help me fix my error? Many thanks!

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  • UPDATE Table SET Field

    - by davlyo
    This is my Very first Post! Bear with me. I have an Update Statement that I am trying to understand how SQL Server handles it. UPDATE a SET a.vField3 = b.vField3 FROM tableName a INNER JOIN tableName b ON a.vField1 = b.vField1 AND b.nField2 = a.nField2 – 1 This is my query in its simplest form. vField1 is a Varchar nField2 is an int (autonumber) vField3 is a Varchar I have left the WHERE clause out so understand there is logic that otherwise makes this a nessessity. Say vField1 is a Customer Number and that Customer has 3 records The value in nField2 is 1, 2, and 3 consecutively. vField3 is a Status When the Update comes to a.nField2 = 1 there is no a.nField2 -1 so it continues When the Update comes to a.nField2 = 2, b.nField2 = 1 When the Update comes to a.nField2 = 3, b.nField2 = 2 So when the Update is on a.nField2 = 2, alias b reflects what is on the line prior (b.nField2 = 1) And it SETs the Varchar Value of a.vField3 = b.vField3 When the Update is on a.nField2 = 3, alias b reflects what is on the line prior (b.nField2 = 2) And it (should) SET the Varchar Value of a.vField3 = b.vField3 When the process is complete –the Second of three records looks as expected –hence the value in vField3 of the second record reflects the value in vField3 from the First record However, vField3 of the Third record does not reflect the value in vField3 from the Second record. I think this demonstrates that SQL Server may be producing a transaction of some sort and then an update. Question: How can I get the DB to Update after each transaction so I can reference the values generated by each transaction?

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  • how to edit controls in a system::thread

    - by Ian Lundberg
    I need to be able to add items to a listbox inside of a thread. Code is below. 1. ref class Work 2. { 3. public: 4. static void RecieveThread() 5. { 6. while (true) 7. { 8. ZeroMemory(cID, 64); 9. ZeroMemory(message, 256); 10. if(recv(sConnect, message, 256, NULL) != SOCKET_ERROR && recv(sConnect, cID, 64, NULL) != SOCKET_ERROR) 11. { 12. ID = atoi(cID); 13. String^ meep = gcnew String(message); 14. lbxMessages->Items->Add(meep); 15. check = 1; 16. } 17. } 18. } 19. }; I get the error Error: a nonstatic member reference must be relative to a specific object on line 14. Is there any way to get it to let me do that? Because if I try to use String^ meep; outside of that Thread it doesn't contain anything. It works PERFECT when I use it within the thread but not outside of it. I need to be able to add that message to the listbox. If anyone can help I would appreciate it.

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  • How to get the parameter names of an object's constructors (reflection)?

    - by Tom
    Say I somehow got an object reference from an other class: Object myObj = anObject; Now I can get the class of this object: Class objClass = myObj.getClass(); Now, I can get all constructors of this class: Constructor[] constructors = objClass.getConstructors(); Now, I can loop every constructor: if (constructors.length > 0) { for (int i = 0; i < constructors.length; i++) { System.out.println(constructors[i]); } } This is already giving me a good summary of the constructor, for example a constructor public Test(String paramName) is shown as public Test(java.lang.String) Instead of giving me the class type however, I want to get the name of the parameter.. in this case "paramName". How would I do that? I tried the following without success: if (constructors.length > 0) { for (int iCon = 0; iCon < constructors.length; iCon++) { Class[] params = constructors[iCon].getParameterTypes(); if (params.length > 0) { for (int iPar = 0; iPar < params.length; iPar++) { Field fields[] = params[iPar].getDeclaredFields(); for (int iFields = 0; iFields < fields.length; iFields++) { String fieldName = fields[i].getName(); System.out.println(fieldName); } } } } } Unfortunately, this is not giving me the expected result. Could anyone tell me how I should do this or what I am doing wrong? Thanks!

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  • .NET List Thread-Safe Implementation Suggestion needed

    - by Bamboo
    .Net List class isn't thread safe. I hope to achieve the minimal lock needed and yet still fulfilling the requirement such that as for reading, phantom record is allowed, and for writing, they must be thread-safe so there won't be any lost updates. So I have something like public static List<string> list = new List<string>(); In Methods that have **List.Add**/**List.Remove** , I always lock to assure thread safety lock (lockHelper) { list.Add(obj); or list.Remove(obj); } In Methods that requires **List Reading** I don't care about phantom record so I go ahead to read without any locking. In this case. Return a bool by checking whether a string had been added. if (list.Count() != 0) { return list.Contains("some string") } All I did was locking write accesses, and allow read accesses to go through without any locking. Is my thread safety idea valid? I understand there is List size expansion. Will it be ok? My guess is that when a List is expanding, it may uses a temp. list. This is ok becasue the temp list size will always have a boundary, and .Net class is well implemented, ie. there shouldn't be any indexOutOfBound or circular reference problems when reading was caught in updates.

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