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  • C#: Basic Reflection Class

    - by Mike
    I'm trying to find a basic reflection abstract class that will generate basic information about a class. I have a template of how I would like it to work: class ThreeList<string,Type,T> { string Name {get; set;} Type Type {get; set;} T Value {get; set;} } abstract class Reflect<T> { List<ThreeList<string, Type, T> list; ReturnType MethodName() { foreach (System.Reflection.PropertyInfo prop in this.GetType().GetProperties()) { object value = prop.GetValue(this, new object[] { }); list.Add(prop.Name, prop.DeclaringType, value); } } } I'd like it to be infinitely deep, recursively calling Reflect. Something like this has to exist. I'm not really opposed to coding it myself, I just don't want to go through the hassle if its already been done.

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  • How to send complete POST to Model in Code Igniter

    - by Constant M
    Hi there, What would be the best way to send a complete post to a model in Code Igniter? Methods I know are as follow: Name form elements as array, eg. <input type="text" name="contact[name]"> <input type="text" name="contact[surname]"> and then use: $this->Model_name->add_contact($this->input->post('contact')); The other would be to add each element to an array and then send it to the model as such: <input type="text" name="name"> <input type="text" name="surname"> and $contact_array = array('name' => $this->input->post('name'), 'surname' => $this->input->post('surname')); $this->Model_name->add_contact($this->input->post('contact')); Which one of these would be best practice, and is there a way to directly send a whole POST to a model (or a whole form maybe?)

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  • Post JSON array to mvc controller

    - by Yustme
    I'm trying to post a JSON array to a mvc controller. But no matter what i try, everything is 0 or null. I have this table that contains textboxes. I need from all those textboxes it's ID and value as an object. This is my java code: $(document).ready(function () { $('#submitTest').click(function (e) { var $form = $('form'); var trans = new Array(); var parameters = { TransIDs: $("#TransID").val(), ItemIDs: $("#ItemID").val(), TypeIDs: $("#TypeID").val(), }; trans.push(parameters); if ($form.valid()) { $.ajax( { url: $form.attr('action'), type: $form.attr('method'), data: JSON.stringify(parameters), dataType: "json", contentType: "application/json; charset=utf-8", success: function (result) { $('#result').text(result.redirectTo) if (result.Success == true) { return fase; } else { $('#Error').html(result.Html); } }, error: function (request) { alert(request.statusText) } }); } e.preventDefault(); return false; }); }); This is my view code: <table> <tr> <th>trans</th> <th>Item</th> <th>Type</th> </tr> @foreach (var t in Model.Types.ToList()) { { <tr> <td> <input type="hidden" value="@t.TransID" id="TransID" /> <input type="hidden" value="@t.ItemID" id="ItemID" /> <input type="hidden" value="@t.TypeID" id="TypeID" /> </td> </tr> } } </table> This is the controller im trying to receive the data to: [HttpPost] public ActionResult Update(CustomTypeModel ctm) { return RedirectToAction("Index"); } What am i doing wrong?

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  • Writing an optimised and efficient search engine with mySQL and ColdFusion

    - by Mel
    I have a search page with the following scenarios listed below. I was told there was a better way to do it, but not how, and that I am using too many if statements, and that it's prone to causing an error through url manipulation: Search.cfm will processes a search made from a search bar present on all pages, with one search input (titleName). If search.cfm is accessed manually (through URL not through using the simple search bar on all pages) it displays an advanced search form with three inputs (titleName, genreID, platformID) or it evaluates searchResponse variable and decides what to do. If simple search query is blank, has no results, or less than 3 characters it displays an error If advanced search query is blank, has no results, or less than 3 characters it displays an error If any successful search returns results, they come back normally. The top-of-page logic is as follows: <!---SET DEFAULT VARIABLE---> <cfparam name="variables.searchResponse" default=""> <!---CHECK TO SEE IF SIMPLE SEARCH A FORM WAS SUBMITTED AND EXECUTE SEARCH IF IT WAS---> <cfif IsDefined("Form.simpleSearch") AND Len(Trim(Form.titleName)) LTE 2> <cfset variables.searchResponse = "invalidString"> <cfelseif IsDefined("Form.simpleSearch") AND Len(Trim(Form.titleName)) GTE 3> <!---EXECUTE METHOD AND GET DATA---> <cfinvoke component="myComponent" method="simpleSearch" searchString="#Form.titleName#" returnvariable="simpleSearchResult"> <cfset variables.searchResponse = "simpleSearchResult"> </cfif> <!---CHECK IF ANY RECORDS WERE FOUND---> <cfif IsDefined("variables.simpleSearchResult") AND simpleSearchResult.RecordCount IS 0> <cfset variables.searchResponse = "noResult"> </cfif> <!---CHECK IF ADVANCED SEARCH FORM WAS SUBMITTED---> <cfif IsDefined("Form.AdvancedSearch") AND Len(Trim(Form.titleName)) LTE 2> <cfset variables.searchResponse = "invalidString"> <cfelseif IsDefined("Form.advancedSearch") AND Len(Trim(Form.titleName)) GTE 2> <!---EXECUTE METHOD AND GET DATA---> <cfinvoke component="myComponent" method="advancedSearch" returnvariable="advancedSearchResult" titleName="#Form.titleName#" genreID="#Form.genreID#" platformID="#Form.platformID#"> <cfset variables.searchResponse = "advancedSearchResult"> </cfif> <!---CHECK IF ANY RECORDS WERE FOUND---> <cfif IsDefined("variables.advancedSearchResult") AND advancedSearchResult.RecordCount IS 0> <cfset variables.searchResponse = "noResult"> </cfif> I'm using the searchResponse variable to decide what the the page displays, based on the following scenarios: <!---ALWAYS DISPLAY SIMPLE SEARCH BAR AS IT'S PART OF THE HEADER---> <form name="simpleSearch" action="search.cfm" method="post"> <input type="hidden" name="simpleSearch" /> <input type="text" name="titleName" /> <input type="button" value="Search" onclick="form.submit()" /> </form> <!---IF NO SEARCH WAS SUBMITTED DISPLAY DEFAULT FORM---> <cfif searchResponse IS ""> <h1>Advanced Search</h1> <!---DISPLAY FORM---> <form name="advancedSearch" action="search.cfm" method="post"> <input type="hidden" name="advancedSearch" /> <input type="text" name="titleName" /> <input type="text" name="genreID" /> <input type="text" name="platformID" /> <input type="button" value="Search" onclick="form.submit()" /> </form> </cfif> <!---IF SEARCH IS BLANK OR LESS THAN 3 CHARACTERS DISPLAY ERROR MESSAGE---> <cfif searchResponse IS "invalidString"> <cfoutput> <h1>INVALID SEARCH</h1> </cfoutput> </cfif> <!---IF SEARCH WAS MADE BUT NO RESULTS WERE FOUND---> <cfif searchResponse IS "noResult"> <cfoutput> <h1>NO RESULT FOUND</h1> </cfoutput> </cfif> <!---IF SIMPLE SEARCH WAS MADE A RESULT WAS FOUND---> <cfif searchResponse IS "simpleSearchResult"> <cfoutput> <h1>Search Results</h1> </cfoutput> <cfoutput query="simpleSearchResult"> <!---DISPLAY QUERY DATA---> </cfoutput> </cfif> <!---IF ADVANCED SEARCH WAS MADE A RESULT WAS FOUND---> <cfif searchResponse IS "advancedSearchResult"> <cfoutput> <h1>Search Results</h1> <p>Your search for "#Form.titleName#" returned #advancedSearchResult.RecordCount# result(s).</p> </cfoutput> <cfoutput query="advancedSearchResult"> <!---DISPLAY QUERY DATA---> </cfoutput> </cfif> Is my logic a) not efficient because my if statements/is there a better way to do this? And b) Can you see any scenarios where my code can break? I've tested it but I have not been able to find any issues with it. And I have no way of measuring performance. Any thoughts and ideas would be greatly appreciated. Many thanks

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  • get greatest prime factor in F#

    - by Alex
    I had VS 11 beta and the following code was working without problem: let rec fac x y = if (x = y) then y elif (x % y = 0I) then fac (x / y) y else fac x / (y + 1I);; Now I installed VS 2012 RC and I get the following error: The type 'System.Numerics.BigInteger -> System.Numerics.BigInteger' is not compatible with the type 'System.Numerics.BigInteger' Is code not correct or F# interactive? It's F# 3.0.

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  • More trivia than really important: Why no new() constraint on Activator.CreateInstance<T>() ?

    - by flq
    I think there are people who may be able to answer this, this is a question out of curiosity: The generic CreateInstance method from System.Activator, introduced in .NET v2 has no type constraints on the generic argument but does require a default constructor on the activated type, otherwise a MissingMethodException is thrown. To me it seems obvious that this method should have a type constraint like Activator.CreateInstance<T>() where T : new() { ... } Just an omission or some anecdote lurking here?

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  • String Index Out Of Bound Exception error

    - by Fd Fehfhd
    Im not really sure why a am getting this error. But here is my code it is meant to test palindromes disregarding punctuation. So here is my code import java.util.Scanner; public class PalindromeTester { public static void main(String [] args) { Scanner kb = new Scanner(System.in); String txt = ""; int left; int right; int cntr = 0; do { System.out.println("Enter a word, phrase, or sentence (blank line to stop):"); txt = kb.nextLine(); txt = txt.toLowerCase(); char yP; String noP = ""; for (int i = 0; i < txt.length(); i++) { yP = txt.charAt(i); if (Character.isLetterOrDigit(txt.charAt(yP))) { noP += yP; } } txt = noP; left = 0; right = txt.length() -1; while (txt.charAt(left) == txt.charAt(right) && right > left) { left++; right--; } if (left > right) { System.out.println("Palindrome"); cntr++; } else { System.out.println("Not a palindrome"); } } while (!txt.equals("")); System.out.println("You found " + cntr + " palindromes. Thank you for using palindromeTester."); } } And if i test it and then i put enter so it will tell me how many palindromes you found the error i am getting is javav.lang.StringIndexOutOfBoundException : String index out of range 0 at PalindromeTester.main(PalindromeTester.java:38) and line 28 is while (txt.charAt(left) == txt.charAt(right) && right > left) Thanks for the help in advance

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  • How can I bind an Enum to a DbType of bit or int?

    - by uriDium
    Hi I am using Linq2Sql and want to bind an objects field (which is enum) to either a bit or a int type in the database. For example I want have a gender field in my model. I have already edited the DBML and changed the Type to point to my enum. I want to create Radio buttons (which I think I have figured out) for gender and dropdown lists for other areas using the same idea. My enum looks like this public enum Gender { Male, Female } Mapping between DbType 'int' and Type 'Project.Models.Gender' in Column 'Gender' of Type 'Candidate' is not supported. Any ideas on how to do this mapping. Am I missing something on the enums.

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  • How to read binary column in database into image on asp.net page?

    - by marko
    I want to read from database where I've stored a image in binary field and display a image. while (reader.Read()) { byte[] imgarr = (byte[])reader["file"]; Stream s = new MemoryStream(imgarr); System.Drawing.Image image = System.Drawing.Image.FromStream(s); Graphics g = Graphics.FromImage(image); g.DrawImage(image, new Point(400, 10)); image.Save(Response.OutputStream, ImageFormat.Jpeg); g.Dispose(); image.Dispose(); } con.Close(); This piece of code doesn't work: System.Drawing.Image image = System.Drawing.Image.FromStream(s); What am I doing wrong?

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  • Output of the following code

    - by terrific
    String s1 = "Amit"; //true String s2 = "Amit"; //true String s3 = new String("abcd"); //true String s4 = new String("abcd"); //false System.out.println(s1.equals(s2)); //true System.out.println((s1==s2)); //true System.out.println(s3.equals(s4)); //false System.out.println((s3==s4)); //false Assume it to be in main why the output of the above code is true true true false and not true true false false???

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  • $ is not defined

    - by coffeeaddict
    I cannot figure out why it's still not recognizing jQuery syntax when I clearly have included the jQuery library right before my $(document).ready <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1"><title> </title></head> <body> <form name="form1" method="post" action="jQueryDialogTest.aspx" id="form1"> <div> <input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwULLTE2MTY2ODcyMjlkZA==" /> </div> <script src="content/js/jquery-1.3.2.min.js" type="text/javascript"></script> <script src="content/js/popup.js" type="text/javascript"></script> <div id="testDialog" winWidth="400" winHeight="500" winResizable="true"> Some test mark-up, should show inside the dialog </div> <div><input type="button" id="invokeDialog" value="Click Me!" /></div> </form> <script type="text/javascript"> $(document).ready(function() { $("input.invokeDialog").click.showDialog("#testDialog"); }); </script> </body> </html>

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  • Doesn't get the output in Java Database Connectivity

    - by Dooree
    I'm working on Java Database Connectivity through Eclipse IDE. I built a database through Ubuntu Terminal, and I need to connect and work with it. However, when I tried to run the following code, I don't get any error, but the following output is showed, anybody knows why I don't get the output from the code ? //STEP 1. Import required packages import java.sql.*; public class FirstExample { // JDBC driver name and database URL static final String JDBC_DRIVER = "com.mysql.jdbc.Driver"; static final String DB_URL = "jdbc:mysql://localhost/EMP"; // Database credentials static final String USER = "username"; static final String PASS = "password"; public static void main(String[] args) { Connection conn = null; Statement stmt = null; try{ //STEP 2: Register JDBC driver Class.forName("com.mysql.jdbc.Driver"); //STEP 3: Open a connection System.out.println("Connecting to database..."); conn = DriverManager.getConnection(DB_URL,USER,PASS); //STEP 4: Execute a query System.out.println("Creating statement..."); stmt = conn.createStatement(); String sql; sql = "SELECT id, first, last, age FROM Employees"; ResultSet rs = stmt.executeQuery(sql); //STEP 5: Extract data from result set while(rs.next()){ //Retrieve by column name int id = rs.getInt("id"); int age = rs.getInt("age"); String first = rs.getString("first"); String last = rs.getString("last"); //Display values System.out.print("ID: " + id); System.out.print(", Age: " + age); System.out.print(", First: " + first); System.out.println(", Last: " + last); } //STEP 6: Clean-up environment rs.close(); stmt.close(); conn.close(); }catch(SQLException se){ //Handle errors for JDBC se.printStackTrace(); }catch(Exception e){ //Handle errors for Class.forName e.printStackTrace(); }finally{ //finally block used to close resources try{ if(stmt!=null) stmt.close(); }catch(SQLException se2){ }// nothing we can do try{ if(conn!=null) conn.close(); }catch(SQLException se){ se.printStackTrace(); }//end finally try }//end try System.out.println("Goodbye!"); }//end main }//end FirstExample <ConnectionProperties> <PropertyCategory name="Connection/Authentication"> <Property name="user" required="No" default="" sortOrder="-2147483647" since="all"> The user to connect as </Property> <Property name="password" required="No" default="" sortOrder="-2147483646" since="all"> The password to use when connecting </Property> <Property name="socketFactory" required="No" default="com.mysql.jdbc.StandardSocketFactory" sortOrder="4" since="3.0.3"> The name of the class that the driver should use for creating socket connections to the server. This class must implement the interface 'com.mysql.jdbc.SocketFactory' and have public no-args constructor. </Property> <Property name="connectTimeout" required="No" default="0" sortOrder="9" since="3.0.1"> Timeout for socket connect (in milliseconds), with 0 being no timeout. Only works on JDK-1.4 or newer. Defaults to '0'. </Property> ...

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  • how to generate JMX MXBean compatible java class model from JAXB?

    - by yucubby
    From the JMX MXBean specification, a java class type J must satisfy Either if J has at least one public constructor with a ConstructorProperties annotation, Or if J has a public no-arg constructor, and for every getter in J with type T and name N there is a corresponding setter with the same name and type So how can I use JAXB to generate JAVA class model which satisfy the MXBean constrain? Thanks YU

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  • Detecting user-activity on mac os x

    - by Nobik
    I use the function "IOPMSchedulePowerEvent" to schedule Sleep or Wake-Events and registered my daemon with "IORegisterForSystemPower" to receive power-state-changes. Everything works fine! When system going sleep and later waking up at scheduled time, my daemon do some work, and after it system should going sleep again. Now my questions: How can i detect, if the system was awaked by user or by the scheduled time? How can i detect, if a user currently working with the system, so the daemon have not to put it in sleep-mode??? Thanks Nobik

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  • Please help with my twodimensional array source code

    - by Baiba
    Here is what i have done but i have some questions: class masivins { public static void main (String args[]) { int mas[][] = {{0, 2, 7, 0, 8, 5, 3}, {0, 4, 0, 6, 0, 0, 0}, {0, 0, 0, 0, 3, 0, 0}, {7, 0, 0, 9, 1, 0, 7}, {5, 0, 4, 0, 0, 2, 0}}; int nulmas[] = new int [7]; int nul=0; for(int j=0; j<7; j++) { nul=0; for(int i=0; i<5; i++) { if(mas[i][j]==0) { nul++; } } nulmas[j]=nul; } for(int i=0; i<5; i++) { for(int j=0; j<7; j++) { System.out.println(mas[i][j]); } System.out.println(); } System.out.println(); for(int i=0; i<5; i++) { System.out.println("Zeros in each array column: " + nulmas[i]); } System.out.println(); } } so my questions are: 1) why after running project there are only 5 "Zeros in each array column....." shown? 2) what and where i need to change in this code to get out the number of column in which zeros are least?

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  • Inconsistent Behavior From Declared DLL Function

    - by Steven
    Why might my GetRawData declared function return a correct value when called from my VB.NET application, but return zero when called from my ASP.NET page? The code is exactly the same except for class type difference (Form / Page) and calling event handler (Form1_Load, Page_Load). Note: In the actual code, #DLL# and #RAWDATAFILE# are both absolute filenames to my DLL and raw data file respectively. Note: The DLL file was not created by Visual Studio. Form1.vb Public Class Form1 Declare Auto Function GetRawData Lib "#DLL#" (ByVal filename() As Byte, _ ByVal byteArray() As Byte, _ ByVal length As Int32) As Int32 Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load Dim buffer(10485760) As Byte Dim msg As String, length As Integer = 10485760 Dim filename As String = "#RAWDATAFILE#" length = GetRawData(Encoding.Default.GetBytes(filename), buffer, length) Default.aspx.vb Partial Public Class _Default Inherits System.Web.UI.Page Declare Auto Function GetRawData Lib "#DLL#" (ByVal filename() As Byte, _ ByVal byteArray() As Byte, _ ByVal length As Int32) As Int32 Protected Sub Page_Load(ByVal sender As Object, _ ByVal e As System.EventArgs) Handles Me.Load Dim buffer(10485760) As Byte Dim msg As String, length As Integer = 10485760 Dim filename As String = "#RAWDATAFILE#" length = GetRawData(Encoding.Default.GetBytes(filename), buffer, length)

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  • How to reliably specialize template with intptr_t in 32 and 64 bit environments?

    - by vava
    I have a template I want to specialize with two int types, one of them plain old int and another one is intptr_t. On 64 bit platform they have different sizes and I can do that with ease but on 32 bit both types are the same and compiler throws an error about redefinition. What can I do to fix it except for disabling one of definitions off with preprocessor? Some code as an example: template<typename T> type * convert(); template<> type * convert<int>() { return getProperIntType(sizeof(int)); } template<> type * convert<intptr_t>() { return getProperIntType(sizeof(intptr_t)); } //this template can be specialized with non-integral types as well, // so I can't just use sizeof() as template parameter. template<> type * convert<void>() { return getProperVoidType(); }

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  • upload form only works in Firefox when uploading ASCII .stl 3D files

    - by NathanPDX
    uploadform.html and upload_file.php (below) works fine in Firefox but fails in Chrome, IE, and Safari when uploading ASCII .stl 3D files. Error message is "Invalid file" and problem occurs with multiple computers and multiple .stl files. When I modify the code to support other file types like JPG and PDF it allows those file types in all three web browsers. Also, Firefox only allows the .stl upload if I include application/octet-stream in the mime types section. Why doesn't this work outside of Firefox? uploadform.html: <!doctype html> <html> <body> <form action="upload_file.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /> <br /> <input type="submit" name="submit" value="Submit" /> </form> </body> </html> upload_file.php: <!doctype html> <html> <body> <?php $allowedExts = array("stl"); $extension = end(explode(".", $_FILES["file"]["name"])); if ( ( ($_FILES["file"]["type"] == "application/sla") || ($_FILES["file"]["type"] == "application/octet-stream") || ($_FILES["file"]["type"] == "text/plain") || ($_FILES["file"]["type"] == "application/unknown") ) && ($_FILES["file"]["size"] < 2000000) && in_array($extension, $allowedExts) ) { if ($_FILES["file"]["error"] > 0) { echo "Return Code: " . $_FILES["file"]["error"] . "<br />"; } else { echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] /1024) . " KB<br />"; if (file_exists("upload/" . $_FILES["file"]["name"])) { echo $_FILES["file"]["name"] . " already exists. "; } else { move_uploaded_file($_FILES["file"]["tmp_name"], "upload/" . $_FILES["file"]["name"]); echo "successful upload"; } } } else { echo "Invalid file"; } ?> </body> </html>

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  • Is my code a correct implementation of insertion sort?

    - by user1657171
    This code sorts correctly. Is this an insertion sort? import java.util.Scanner; public class InsertionSort { public static void main(String[] args) { Scanner sc = new Scanner(System.in); System.out.println("Enter the number of elements: "); int count; count = sc.nextInt(); int[] a = new int[count]; System.out.println("Enter elements: "); for(int i = 0 ; i<count;i++){ a[i] = sc.nextInt(); } int j,temp; System.out.println("aftr insertion sort :"); for(int i = 1 ; i<count;i++){ j=i; while(j>0 && a[j-1] > a[j] ){ temp = a[j]; a[j] = a[j-1]; a[j-1] = temp; j--; } } for(int i = 0 ; i<count;i++){ System.out.print(a[i]+" "); } } }

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  • How does ambigous methods are resolved in java ?

    - by Jijoy
    Hi , I do have a question. package org.study.algos; public class Study { public static void main(String[] args) { A a = new A(); a.m1(null); } } class A { public void m1(String s) { System.out.println("String"); System.out.println(s); } public void m1(Object obj) { System.out.println("Object"); System.out.println(obj); } } Here , the output is String null Why JVM resolve the method to one with String arguement ? Thanks in advance J

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  • Multiple datepicker problem with same ID

    - by namezero
    hi, here is my problem: <input type="text" class="datepick1" id="date" /> <input type="text" class="datepick2" id="date" /> <input type="text" class="datepick3" id="date" /> then i apply datepicker on dom (by classname) $('.datepick1').datepicker(); $('.datepick2').datepicker(); $('.datepick3').datepicker(); = the three dom have datepicker but, onselect date, it change automatically the first one (datepick1) HELP

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  • How to dynamically use the PropertyType reflection attribute to create a respective typed Function<

    - by vsj
    I want to use type returned by PropertyType to create a typed function. I found this similiar http://stackoverflow.com/questions/914578/using-type-returned-by-type-gettype-in-c but this mentions how to create a list but does not mention how we can create a Func<. Please help me out. Pseudocode: PropertyInfo inf = typeof(SomeClass).GetProperty("PropertyName"); Type T=inf.PropertyType; Expression<Func<SomeClass,T>> le = GetPropertyOrFieldByName<SomeClass, T>("PropertyName");

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  • Parameter pack argument consumption

    - by yuri kilochek
    It is possible to get the first element of the parameter pack like this template <typename... Elements> struct type_list { }; template <typename TypeList> struct type_list_first_element { }; template <typename FirstElement, typename... OtherElements> struct type_list_first_element<type_list<FirstElement, OtherElements...>> { typedef FirstElement type; }; int main() { typedef type_list<int, float, char> list; typedef type_list_first_element<list>::type element; return 0; } but not possible to similary get the last element like this template <typename... Elements> struct type_list { }; template <typename TypeList> struct type_list_last_element { }; template <typename LastElement, typename... OtherElements> struct type_list_last_element<type_list<OtherElements..., LastElement>> { typedef LastElement type; }; int main() { typedef type_list<int, float, char> list; typedef type_list_last_element<list>::type element; return 0; } with gcc 4.7.1 complaining: error: 'type' in 'struct type_list_last_element<type_list<int, float, char>>' does not name a type What paragraps from the standard describe this behaviour? It seems to me that template parameter packs are greedy in a sense that they consume all matching arguments, which in this case means that OtherElements consumes all three arguments (int, float and char) and then there is nothing left for LastElement so the compilation fails. Am i correct in the assumption? EDIT: To clarify: I am not asking how to extract the last element from the parameter pack, i know how to do that. What i actually want is to pick the pack apart from the back as opposed to the front, and as such recursing all the way to the back for each element would be ineffective. Apparentely reversing the sequence beforehand is the most sensible choice.

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  • Concept: Information Into Memory Location.

    - by Richeve S. Bebedor
    I am having troubles conceptualizing an algorithm to be used to transform any information or data into a specific appropriate and reasonable memory location in any data structure that I will be devising. To give you an idea, I have a JPanel object instance and I created another Container type object instance of any subtype (note this is in Java because I love this language), then I collected those instances into a data structure not specifically just for those instances but also applicable to any type of object. Now my procedure for fetching those data again is to extract the object specific features similar in category to all object in that data structure and transform it into a integer data memory location (specifically as much as possible) or any type of data that will pertain to this transformation. And I can already access that memory location without further sorting or applications of O(n) time complex algorithms (which I think preferable but I wanted to do my own way XD). The data structure is of any type either binary tree, linked list, arrays or sets (and the like XD). What is important is I don't need to have successive comparing and analysis of data just to locate information in big structures. To give you a technical idea, I have to an array DS that contains JLabel object instance with a specific name "HelloWorld". But array DS contains other types of object (in multitude). Now this JLabel object has a location in the array at index [124324] (which is if you do any type of searching algorithm just to arrive at that location is conceivably slow because added to it the data structure used was an array *note please disregard the efficiency of the data structure to be used I just want to explain to you my concept XD). Now I want to equate "HelloWorld" to 124324 by using a conceptually made function applicable to all data types. So that I can do a direct search by doing this DS[extractLocation("HelloWorld")] just to get that JLabel instance. I know this may sound crazy but I want to test my concept of non-sorting feature extracting search algorithm for any data structure wherein my main problem is how to transform information to be stored into memory location of where it was stored.

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