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  • Mixing JSP/HTML any new features or suggestions

    - by Maglebolia
    Hi all, I have a Web-Application, which is mainly JSP (file extension) and is including some HTML. It seems to me that the "general" way is "old" and not always well red by some IDE like Eclipse: Is there no other way to include jsp expression with "<% ... %". There is no need for a framework to resolve this, since we only have like 60 pages. I run through examples and see that we can seperate the code with blockquotes "< script < /script ". I'm really wondering which is the better method for understanding and easier reading of the code. Any formatting, syntax coloring, plugin or new code style suggestions would help. Here an example <%} %> <%if(condition) { %> <tr> <td class="label"><%=method()%></td> <td class="text"><%=method()%></td> </tr> <%} %> <tr>

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  • small code redundancy within while-loops (doesn't feel clean)

    - by wallacoloo
    So, in Python (though I think it can be applied to many languages), I find myself with something like this quite often: the_input = raw_input("what to print?\n") while the_input != "quit": print the_input the_input = raw_input("what to print?\n") Maybe I'm being too picky, but I don't like how the line the_input = raw_input("what to print?\n") has to get repeated. It decreases maintainability and organization. But I don't see any workarounds for avoiding the duplicate code without further decreasing the problem. In some languages, I could write something like this: while ((the_input=raw_input("what to print?\n")) != "quit") { print the_input } This is definitely not Pythonic, and Python doesn't even allow for assignment within loop conditions AFAIK. This valid code fixes the redundancy, while 1: the_input = raw_input("what to print?\n") if the_input == "quit": break print the_input But doesn't feel quite right either. The while 1 implies that this loop will run forever; I'm using a loop, but giving it a fake condition and putting the real one inside it. Am I being too picky? Is there a better way to do this? Perhaps there's some language construct designed for this that I don't know of?

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  • nginx multiple domain virtual host configuration

    - by Poe
    I'm setting up nginx with multiple domain or wildcard support for convenience sake, rather than setting up 50+ different sites-available/* files. Hopefully this is enough to show you what I'm trying to do. Some are static sites, some are dynamic with usually wordpress installed. If an index.php exists, everything works as expected. If a file is requested that does not exist (missing.html), a 500 error is given due to the rewrite. The logged error is: *112 rewrite or internal redirection cycle while processing "/index.php/index.php/index.php/index.php/index.php/index.php/index.php/index.php/index.php/index.php/index.php/missing.html" The basic nginx configuration I'm currently using is: ` listen 80 default; server _; ... location / { root /var/www/$host; if (-f $request_filename) { expires max; break; } # problem, what if index.php does not exist? if (!-e $request_filename) { rewrite ^/(.*)$ /index.php/$1 last; } } ... ` If an index.php does not exist, and the file also does not exist, I would like it to error 404. Currently, nginx does not support multiple condition if's or nested if so I need a workaround.

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  • JSF: Avoid nested update calls

    - by dhroove
    I don't know if I am on right track or not still asking this question. I my JSF project I have this tree structure: <p:tree id="resourcesTree" value="#{someBean.root}" var="node" selectionMode="single" styleClass="no-border" selection="#{someBean.selectedNode}" dynamic="true"> <p:ajax listener="#{someBean.onNodeSelect}" update=":centerPanel :tableForm :tabForm" event="select" onstart="statusDialog.show();" oncomplete="statusDialog.hide();" /> <p:treeNode id="resourcesTreeNode" > <h:outputText value="#{node}" id="lblNode" /> </p:treeNode> </p:tree> I have to update this tree after I added something or delete something.. But whenever I update this still its nested update also call I mean to say it also call to update these components ":centerPanel :tableForm :tabForm"... This give me error that :tableForm not found in view because this forms load in my central panel and this tree is in my right panel.. So when I am doing some operation on tree is it not always that :tableForm is in my central panel.. (I mean design is something like this only) So now my question is that can I put some condition or there is any way so that I can specify when to update nested components also and when not.... In nut shell is there any way to update only :resoucesTree is such a way that nested updates are not called so that I can avoid error... Thanks in advance.

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  • Struts2 Converting Enum Array fills array with single null value

    - by Kyle Partridge
    For a simple action class with these member variables: ... private TestConverterEnum test; private TestConverterEnum[] tests; private List<TestConverterEnum> tList; ... And a simple enum: public enum TestConverterEnum { A, B, C; } Using the default struts2 enum conversion, when I send the request like so: TestConterter.action?test=&tests=&tList=&b=asdf For test I get a null value, which is expected. For the Array and List, however, I get and Array (or list) with one null element. Is this what is expected? Is there a way to prevent this. We recently upgraded our struts2 version, and we had our own converters, which also don't work in this case, so I was hoping to use the default conversion method. We already have code that is validating these arrays for null and length, and I don't want to have to add another condition to these branches. Is there a way to prevent this bevavior?

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  • determine page UI culture throgh javascript

    - by mj-y
    I have two div tags in my html code as shown below. I want to change their float property depending on page UI culture ( Ui culture is en-US or fa-IR) ... I think I can use java script to do so. but I don't know how can I get the UI Culture through Javascript. I want a code in if condition to determine the Ui culture ... thx in advance for your help... <div id="zone1" style="float: left;"><img alt="" src="~/IconArrow.png" /> &nbsp;</div> <div id="zone2" style="float: left;"><img alt="" src="~/IconHome.png" /></div> <script type="text/javascript"> if(/* ui culture is fa-IR*/) { document.getElementById("zone1").style.float = "right"; document.getElementById("zone2").style.float = "right"; } </script>

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  • Conversion failed when converting the varchar value to int

    - by onedaywhen
    Microsoft SQL Server 2008 (SP1), getting an unexpected 'Conversion failed' error. Not quite sure how to describe this problem, so below is a simple example. The CTE extracts the numeric portion of certain IDs using a search condition to ensure a numeric portion actually exists. The CTE is then used to find the lowest unused sequence number (kind of): CREATE TABLE IDs (ID CHAR(3) NOT NULL UNIQUE); INSERT INTO IDs (ID) VALUES ('A01'), ('A02'), ('A04'), ('ERR'); WITH ValidIDs (ID, seq) AS ( SELECT ID, CAST(RIGHT(ID, 2) AS INTEGER) FROM IDs WHERE ID LIKE 'A[0-9][0-9]' ) SELECT MIN(V1.seq) + 1 AS next_seq FROM ValidIDs AS V1 WHERE NOT EXISTS ( SELECT * FROM ValidIDs AS V2 WHERE V2.seq = V1.seq + 1 ); The error is, 'Conversion failed when converting the varchar value 'RR' to data type int.' I can't understand why the value ID = 'ERR' should be being considered for conversion because the predicate ID LIKE 'A[0-9][0-9]' should have removed the invalid row from the resultset. When the base table is substituted with an equivalent CTE the problem goes away i.e. WITH IDs (ID) AS ( SELECT 'A01' UNION ALL SELECT 'A02' UNION ALL SELECT 'A04' UNION ALL SELECT 'ERR' ), ValidIDs (ID, seq) AS ( SELECT ID, CAST(RIGHT(ID, 2) AS INTEGER) FROM IDs WHERE ID LIKE 'A[0-9][0-9]' ) SELECT MIN(V1.seq) + 1 AS next_seq FROM ValidIDs AS V1 WHERE NOT EXISTS ( SELECT * FROM ValidIDs AS V2 WHERE V2.seq = V1.seq + 1 ); Why would a base table cause this error? Is this a known issue? UPDATE @sgmoore: no, doing the filtering in one CTE and the casting in another CTE still results in the same error e.g. WITH FilteredIDs (ID) AS ( SELECT ID FROM IDs WHERE ID LIKE 'A[0-9][0-9]' ), ValidIDs (ID, seq) AS ( SELECT ID, CAST(RIGHT(ID, 2) AS INTEGER) FROM FilteredIDs ) SELECT MIN(V1.seq) + 1 AS next_seq FROM ValidIDs AS V1 WHERE NOT EXISTS ( SELECT * FROM ValidIDs AS V2 WHERE V2.seq = V1.seq + 1 );

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  • problem with fork()

    - by john
    I'm writing a shell which forks, with the parent reading the input and the child process parsing and executing it with execvp. pseudocode of main method: do{ pid = fork(); print pid; if (p<0) { error; exit; } if (p>0) { wait for child to finish; read input; } else { call function to parse input; exit; } }while condition return; what happens is that i never seem to enter the child process (pid printed is always positive, i never enter the else). however, if i don't call the parse function and just have else exit, i do correctly enter parent and child alternatingly. full code: int main(int argc, char *argv[]){ char input[500]; pid_t p; int firstrun = 1; do{ p = fork(); printf("PID: %d", p); if (p < 0) {printf("Error forking"); exit(-1);} if (p > 0){ wait(NULL); firstrun = 0; printf("\n> "); bzero(input, 500); fflush(stdout); read(0, input, 499); input[strlen(input)-1] = '\0'; } else exit(0); else { if (parse(input) != 0 && firstrun != 1) { printf("Error parsing"); exit(-1); } exit(0); } }while(strcmp(input, "exit") != 0); return 0; }

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  • How can I get the main thread to sleep while waiting for a delgate to be called?

    - by Erik B
    Consider a class with these methods: - (id) initWithFrame: (CGRect) frame { if (!(self = [super init])) return nil; webView = [[UIWebView alloc] initWithFrame:frame]; [webView setDelegate:self]; lock = [[NSConditionLock alloc] initWithCondition:LOCK_WAIT]; return self; } - (void) setHTML: (NSString *) html { [lock lockWhenCondition:LOCK_WAIT]; [webView loadHTMLString:html baseURL:nil]; [lock unlock]; } - (void)webViewDidFinishLoad:(UIWebView *)aWebView { [lock lockWhenCondition:LOCK_WAIT]; // Locking to be able to unlock and change the condition. [lock unlockWithCondition:LOCK_GO]; } - (NSString *) stringByEvaluatingJavaScriptFromString: (NSString *) jsCommand { [lock lockWhenCondition:LOCK_GO]; return [webView stringByEvaluatingJavaScriptFromString:jsCommand]; [lock unlock]; } Let's call this class SynchronousUIWebView. From the main thread I execute: webView = [[SynchronousUIWebView alloc] initWithFrame:frame]; [webView setHTML:html]; [webView stringByEvaluatingJavaScriptFromString:jsCommand]; The problem seems to be that the delegate is not called until I leave the current call stack, which I don't since I'm waiting for the delegate call to happen, aka deadlock. To me it seems like the delegate call is pushed to a queue that is called when the current call is done. So the question is can I modify this behavior? Note: The reason this is needed is that I can't execute the JavaScript until the HTML has loaded.

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  • Show/hide text based on optgroup selection using Jquery

    - by general exception
    I have the following HTML markup:- <select name="Fault" class="textbox" id="fault"> <option>Single Light Out</option> <option>Light Dim</option> <option>Light On In Daytime</option> <option>Erratic Operating Times</option> <option>Flashing/Flickering</option> <option>Causing Tv/Radio Interference</option> <option>Obscured By Hedge/Tree Branches</option> <option>Bracket Arm Needs Realigning</option> <option>Shade/Cover Missing</option> <option>Column In Poor Condition</option> <option>Several Lights Out (please state how many)</option> <option>Column Leaning</option> <option>Door Missing/Wires Exposed</option> <option>Column Knocked Down/Traffic Accident</option> <option>Lantern Or Bracket Broken Off/Hanging On Wires</option> <option>Shade/Cover Hanging Open</option> </select> <span id="faulttext" style="color:Red; display:none">Text in the span</span> This Jquery snippet adds the last 5 options into an option group. $('#fault option:nth-child(n+12)').wrapAll('<optgroup label="Urgent Reasons">'); What I want to do is, remove the display:none if any of the items within the <optgroup> are selected, effectively displaying the span message, possibly with a fade in transition, and also hide the message if any options outside of the <optgroup> are selected.

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  • Why do InterruptedExceptions clear a thread's interrupted status?

    - by Hanno Fietz
    If a thread is interrupted while inside Object.wait() or Thread.join(), it throws an InterruptedException, which resets the thread's interrupted status. I. e., if I have a loop like this inside a Runnable.run(): while (!this._workerThread.isInterrupted()) { // do something try { synchronized (this) { this.wait(this._waitPeriod); } } catch (InterruptedException e) { if (!this._isStopping()) { this._handleFault(e); } } } the thread will continue to run after calling interrupt(). This means I have to explicitly break out of the loop by checking for my own stop flag in the loop condition, rethrow the exception, or add a break. Now, this is not exactly a problem, since this behaviour is well documented and doesn't prevent me from doing anything the way I want. However, I don't seem to understand the concept behind it: Why is a thread not considered interrupted anymore once the exception has been thrown? A similar behaviour also occurs if you get the interrupted status with interrupted() instead of isInterrupted(), then, too, the thread will only appear interrupted once. Am I doing something unusual here? For example, is it more common to catch the InterruptedException outside the loop? (Even though I'm not exactly a beginner, I tagged this "beginner", because it seems like a very basic question to me, looking at it.)

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  • Opening my application when a usb device is inserted on Windows using WMI

    - by rsteckly
    Hi, I'm trying to launch an event when someone plugs in a usb device. For now, I'm content to simply print something to the console (in the finished product, it will launch an application). This code is very loosely adapted from: http://serverfault.com/questions/115496/use-wmi-to-detect-a-usb-drive-was-connected-regardless-of-whether-it-was-mounted There's two problems: 1) I need to pass the argument to Management scope dynamically because this will be installed on computers I don't use or whose name I don't know. 2) I'm getting an invalid namespace exception when I call w.Start(); Any ideas what I'm doing wrong? static ManagementEventWatcher w=null; static void Main(string[] args) { AddInstUSBHandler(); for(;;); } public static void USBRemoved(object sneder, EventArgs e) { Console.WriteLine("A USB device inserted"); } static void AddInstUSBHandler() { WqlEventQuery q; ManagementScope scope = new ManagementScope("HQ\\DEV1"); scope.Options.EnablePrivileges=true; q=new WqlEventQuery(); q.EventClassName+="_InstanceCreationEvent"; q.WithinInterval=new TimeSpan(0,0,3); q.Condition=@"TargetInstance ISA 'Win32_USBControllerdevice'"; w=new ManagementEventWatcher(scope,q); w.EventArrived+=new EventArrivedEventHandler(USBRemoved); w.Start(); }

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  • Adding <tr> from repeater's ItemDataBound Event

    - by nemiss
    My repeater's templates generate a table, where each item is a table row. When a very very specific condition is met (itemdata), I want to add an additional row to the table from this event. How can I do that? protected void rptData_ItemDataBound(object sender, RepeaterItemEventArgs e) { if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem) { bool tmp = bool.Parse(DataBinder.Eval(e.Item.DataItem, "somedata").ToString()); if (!tmp && e.Item.ItemIndex != 0) { //Add row after this item } } } I can use e.Item.Controls.Add() and add TableRow but for that I need to locate a table right? How can I solve that? UPDATE I will explain now why I need this: I am creating a sort of message board, where data entries are displayed in a tabled style. The first items in the table are "important" items after those items, i want to add this row. I could solved it using 2 repeaters, where the first repeater will be bounded to pinned items, and the second repeater will be bounded to refular items. But I don't want to have to repeaters nor I want to complex the business logic for separating the fetched data to pinned and not-pinned collection. I think the best opton is to do it "onfly", using one repeater and one datasource.

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  • javascript error handeling

    - by pankaj
    I have a javascript function for checking errors which i am callin on OnClicentClick event of a button. Once it catch a error i want to stop execution of click event . But in my case it always it always executes the onclick event. Following is my function: function DisplayError() { if (document.getElementById('<%=txtPassword.ClientID %>').value.length < 6 || document.getElementById('<%=txtPassword.ClientID %>').value.length > 12) { document.getElementById('<%=lblError.ClientID %>').innerText = "Password length must be between 6 to 12 characters"; return false; } var str = <%=PhoneNumber()%>; if(str.length <10) { alert('<%=phoneNum%>'.length); document.getElementById('<%=lblError.ClientID %>').innerText = "Phone Number not in correct format"; return false; } } button html code: <asp:Button runat="server" Text="Submit" ID="btnSubmit" ValidationGroup="submit" onclick="btnSubmit_Click" OnClientClick="DisplayError()"/> It should not execute the button click event once it satisfies any of the IF condition in javascript function.

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  • PHP Commercial Project Function define

    - by Shiro
    Currently I am working with a commercial project with PHP. I think this question not really apply to PHP for all programming language, just want to discuss how your guys solve it. I work in MVC framework (CodeIgniter). all the database transaction code in model class. Previously, I seperate different search criteria with different function name. Just an example function get_student_detail_by_ID($id){} function get_student_detail_by_name($name){} as you can see the function actually can merge to one, just add a parameter for it. But something you are rushing with project, you won't look back previously got what similar function just make some changes can meet the goal. In this case, we found that there is a lot function there and hard to maintenance. Recently, we try to group the entity to one ultimate search something like this function get_ResList($is_row_count=FALSE, $record_start=0, $arr_search_criteria='', $paging_limit=20, $orderby='name', $sortdir='ASC') we try to make this function to fit all the searching criteria. However, our system getting bigger and bigger, the search criteria not more 1-2 tables. It require join with other table with different purpose. What we had done is using IF ELSE, if(bla bla bla) { $sql_join = JOIN_SOME_TABLE; $sql_where = CONDITION; } at the end, we found that very hard to maintance the function. it is very hard to debug as well. I would like to ask your opinion, what is the commercial solution they solve this kind of issue, how to define a function and how to revise it. I think this is link project management skill. Hope you willing to share with us. Thanks.

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  • spyr validation text with jquery serialize()

    - by oz1453
    Code like this : <form> <ol> <li> <fieldset> <legend>test</legend> <ol> <li> <label for="qwerty">qwerty</label> <span id="sprytextfield1"> <input name="qwerty" type="text" id="qwerty" /> <span class="textfieldRequiredMsg">error no qwerty input</span></span> </li> </ol> </fieldset> </li> </ol> <p style="text-align:right;"> <input type="reset" value="reset" /> <input type="submit" value="submit" /> </p> </form> <script type="text/javascript"> $('form').submit(function() { alert($(this).serialize()); return false; }); <!-- var sprytextfield1 = new Spry.Widget.ValidationTextField("sprytextfield1", "none", {validateOn:["blur"]}); //--> </script> I want to do. when i click the submit button serialize the form but when no error with spyr. if the spyr validation text error appears don t serialize or alert. i think.i must make a if condition before alert.

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  • Prime Numbers in C?

    - by Ali Azam Rana
    FIRST PROGRAM #include<stdio.h> void main() { int n,c; printf("enter a numb"); scanf("%i",n); for(c=2;c<=n;c++) { if(n%c==0) break; } if(c==n) printf("\nprime\n"); else printf("\nnot prime\n"); getchar(); } SECOND PROGRAM #include <stdio.h> int main() { printf("Enter a Number\n"); int in,loop,rem,chk; scanf("%d",&in); for (loop = 1; loop <=in; loop++) { rem = in % loop; if(rem == 0) chk = chk +1; } if (chk == 2) printf("\nPRIME NUM ENTERED\n"); else printf("\nNUM ENTERED NOT PRIME\n"); getchar(); } the 2nd program works other was the one my friend wrote the program looks fine but on checking it by stepping into we found that the if condition in first program is coming true under every input so whats the logical error here please help me found out......

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  • safe placement new & explicit destructor call

    - by uray
    this is an example of my codes: ` template <typename T> struct MyStruct { T object; } template <typename T> class MyClass { MyStruct<T>* structPool; size_t structCount; MyClass(size_t count) { this->structCount = count; this->structPool = new MyStruct<T>[count]; for( size_t i=0 ; i<count ; i++ ) { //placement new to call constructor new (&this->structPool[i].object) T(); } } ~MyClass() { for( size_t i=0 ; i<this->structCount ; i++ ) { //explicit destructor call this->structPool[i].object.~T(); } delete[] this->structPool; } } ` my question is, is this a safe way to do? do I make some hidden mistake at some condition? will it work for every type of object (POD and non-POD) ?

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  • How to insert zeros between bits in a bitmap?

    - by anatolyg
    I have some performance-heavy code that performs bit manipulations. It can be reduced to the following well-defined problem: Given a 13-bit bitmap, construct a 26-bit bitmap that contains the original bits spaced at even positions. To illustrate: 0000000000000000000abcdefghijklm (input, 32 bits) 0000000a0b0c0d0e0f0g0h0i0j0k0l0m (output, 32 bits) I currently have it implemented in the following way in C: if (input & (1 << 12)) output |= 1 << 24; if (input & (1 << 11)) output |= 1 << 22; if (input & (1 << 10)) output |= 1 << 20; ... My compiler (MS Visual Studio) turned this into the following: test eax,1000h jne 0064F5EC or edx,1000000h ... (repeated 13 times with minor differences in constants) I wonder whether i can make it any faster. I would like to have my code written in C, but switching to assembly language is possible. Can i use some MMX/SSE instructions to process all bits at once? Maybe i can use multiplication? (multiply by 0x11111111 or some other magical constant) Would it be better to use condition-set instruction (SETcc) instead of conditional-jump instruction? If yes, how can i make the compiler produce such code for me? Any other idea how to make it faster? Any idea how to do the inverse bitmap transformation (i have to implement it too, bit it's less critical)?

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  • Can't seem to sign AWS Cloud Front URL properly

    - by Joe Corkery
    Hi everybody, I found a lot of detailed examples online on how to sign an Amazon CloudFront URL for private content. Unfortunately, whenever I implement these examples my URL doesn't seem to work. The resource path is correct because I can download the file when it is set for world read, but the URL doesn't work when set just for authorized users. The PHP code I am using is below. If anybody has any insights as to what I might be doing wrong (I'm guessing it is something obvious that I am just not seeing right now), it would be greatly appreciated. function urlCloudFront($resource) { $AWS_CF_KEY = 'APKA...'; $priv_key = file_get_contents(path_to_pem_file); $pkeyid = openssl_get_privatekey($priv_key); $expires = strtotime("+ 3 hours"); $policy_str = '{"Statement":[{"Resource":"'.$resource.'","Condition":{"DateLessThan":{"AWS:EpochTime":'.$expires.'}}}]}'; $policy_str = trim( preg_replace( '/\s+/', '', $policy_str ) ); $res = openssl_sign($policy_str, $signature, $pkeyid, OPENSSL_ALGO_SHA1); $signature_base64 = (base64_encode($signature)); $repl = array('+' => '-','=' => '_','/' => '~'); $signature_base64 = strtr($signature_base64,$repl); $url = $resource . '?Expires=' .$expires. '&Signature=' . $signature_base64 . '&Key-Pair-Id='. $AWS_CF_KEY; print '<p><A href="' .$url. '">Download VIDA (CloudFrount)</A>'; } urlCloudFront("http://mydistcloud.cloudfront.net/mydir/myfile.tar.gz"); Thanks.

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  • Telerik RadGrid: grid clientside pagination

    - by ram
    I have a web service which returns me some data,I am massaging this data and using this as datasource for my radgrid (telerik). The datasource is quite large, and would like to paginate it. I found couple of problems when I paginate it in the server side I have to bind the grid again for pagination, which essentially means I have to make a call to WS again to get the data. This is an expensive call for me. I would rather forgo the benefits of pagination and would display all the results in the same page, except for it would be a bit clumsy During the postback RadGrid1.Items.Count happens to be the number of items getting paginated (25- in my case) which is expected as all the items in the datasource are not getting bound. This of course is not an issue. The real issue is that we have some checkboxes which get checked based on some business condition. We add this to our business object/DB later. So if the user has not navigated all the pages, these "checked" items do not get added as pagination limits the "Items" in the grid to those which get bound for that particular page index. My Thoughts: I would rather have some sort of client side pagination, where we can hide/show contents than going to the server and doing a databind every time. Though it will return all the results, the UI will not be clumsy and the grid would have "all the items" during postback Is there a way to do it ? If it were a regular asp.net gridView, can someone point me to a good article which would serve my purpose Ram PS: who else think radgrid is crazy ? (unfortunately I did not make this choice)

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  • Practice of checking 'trueness' or 'equality' in conditional statements - does it really make sense?

    - by Senthil
    I remember many years back, when I was in school, one of my computer science teachers taught us that it was better to check for 'trueness' or 'equality' of a condition and not the negative stuff like 'inequality'. Let me elaborate - If a piece of conditional code can be written by checking whether an expression is true or false, we should check the 'trueness'. Example: Finding out whether a number is odd - it can be done in two ways: if ( num % 2 != 0 ) { // Number is odd } or if ( num % 2 == 1 ) { // Number is odd } When I was beginning to code, I knew that num % 2 == 0 implies the number is even, so I just put a ! there to check if it is odd. But he was like 'Don't check NOT conditions. Have the practice of checking the 'trueness' or 'equality' of conditions whenever possible.' And he recommended that I use the second piece of code. I am not for or against either but I just wanted to know - what difference does it make? Please don't reply 'Technically the output will be the same' - we ALL know that. Is it a general programming practice or is it his own programming practice that he is preaching to others?

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  • Which database I can used and relationship in it ??

    - by mimo-hamad
    My projece make me confused which I didn't find clear things that make me understand the required database and the relationships in it So, would a super one help me to solve it ?!! ;D this is required: 1) Model the data stored in the database (Identify the entities, roles, relationships, constraints, etc.) 2) Write the Oracle commands to create the database, find appropriate data, and populate the database 3) Write five different queries on your database, using the SELECT/FROM/WHERE construct provided in SQL. Your five queries should illustrate several different aspects of database querying, such as: a. Queries over more than one relation (by listing more than one relation in the FROM clause) b. Queries involving aggregate functions, such as SUM, COUNT, and AVG c. Queries involving complicated selects and joins d. Queries involving GROUP BY, HAVING or other similar functions. e. Queries that require the use of the DISTINCT keyword. And this the condition that we need to determine it to solve the required Q's above : 5) It is desired to develop an Internet membership club to buy products at special prices online. To join, new members must be referred by another existing member of the club. The system will keep the following information for each member: The member ID, referring member, birth date, member name, address, phone, mobile, credit card type, number and expiration date. The items are always shipped to the member's address noted in the membership application. The shipping fees will differ for each order.For each item to be requested, the member will select an item from a long list of possible items. For each item in the database, we store an item ID, an item name, description, and list price. The list price will be different from the actual sale price. The available quantity and the back-ordered quantity (the back-ordered quantity is the quantity on-order by the club from its suppliers) is also noted

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  • Rails: using find method to access joined tables for polymorphic relationships

    - by DJTripleThreat
    Ok, I have a generic TimeSlot model that deals with a start_at and an end_at for time spans. A couple models derive from this but I'm referring to one in this question: AppointmentBlock which is a collection of Appointments. I want to validate an AppointmentBlock such that no other AppointmentBlocks have been scheduled for a particular Employee in the same time frame. Since AppointmentBlock has a polymorphic association with TimeSlot, you have to access the AppointmentBlock's start_at and end_at through the TimeSlot like so: appt_block.time_slot.start_at This means that I need to have some kind of join in my :conditions for my find() method call. Here is my code so far: #inside my appointment_block.rb model validate :employee_not_double_booked def employee_not_double_booked unless self.employee_id # this find's condition is incorrect because I need to join time_slots to get access # to start_at and end_at. How can I do this? blocks = AppointmentBlock.find(:first, :conditions => ['employee_id = ? and (start_at between ? and ? or end_at between ? and ?)', self.employee_id, self.time_slot.start_at, self.time_slot.end_at, self.time_slot.start_at, self.time_slot.end_at]) # pseudo code: # collect a list of appointment blocks that end after this # apointment block starts or start before this appointment # block ends that are also associated with this appointment # blocks assigned employee # if the count is great then 0 the employee has been double # booked. # if a block was found that means this employee is getting # double booked so raise an error errors.add "AppointmentBlock", "has already been scheduled during this time" if blocks end end Since AppointmentBlock doesn't have a start_at or an end_at how can I join with the time_slots table to get those conditions to work?

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  • SSRS How to access the current value within a list control?

    - by Dale Burrell
    In SQL Server Reporting Services I have a report which has a list control which groups on currency. Within the list control I display the detailed rows of all records filtered to those with a value = £500. i.e. the top earners. However for each row I need to calculate the percentage of its amount over the total of the entire dataset. Because I am filtering it I can't use Sum(Fields!Amount.Value) as that only sums the data after filtering, so I am trying a conditional sum over the entire dataset, but am struggling with the correct condition e.g =100.00*Fields!Amount.Value/Sum((IIf(Fields!Currency.Value = "£", Fields!Amount.Value, CDec(0))),"DataSet") So where the hardcoded currency symbol is I need to access the current value of currency for the list control, but because my sum is scoped at dataset level any field access is dataset level. Ideally I'd like something like the following, otherwise any other ideas on how to solve this problem. =100.00*Fields!Amount.Value/Sum((IIf(Fields!Currency.Value = myListControl.Value, Fields!Amount.Value, CDec(0))),"DataSet") In fact, thinking about it, it would work if I just could access the row level data at that point, but how to do that when its at dataset scope within the sum statement? Hope that makes sense, any help appreciated.

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