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  • File Segmentation when trying to write in a file

    - by user1286390
    I am trying in C language to use the method of bisection to find the roots of some equation, however when I try to write every step of this process in a file I get the problem "Segmentation fault". This might be an idiot fault that I did, however I have been trying to solve this for a long time. I am compiling using gcc and that is the code: #include <stdio.h> #include <stdlib.h> #include <math.h> #define R 1.0 #define h 1.0 double function(double a); void attractor(double *a1, double *a2, double *epsilon); void attractor(double *a1, double *a2, double *epsilon) { FILE* bisection; double a2_copia, a3, fa1, fa2; bisection = fopen("bisection-part1.txt", "w"); fa1 = function(*a1); fa2 = function(*a2); if(function(*a1) - function(*a2) > 0.0) *epsilon = function(*a1) - function(*a2); else *epsilon = function(*a2) - function(*a1); fprintf(bisection, "a1 a2 fa1 fa2 epsilon\n"); a2_copia = 0.0; if(function(*a1) * function(*a2) < 0.0 && *epsilon >= 0.00001) { a3 = *a2 - (*a2 - *a1); a2_copia = *a2; *a2 = a3; if(function(*a1) - function(*a2) > 0.0) *epsilon = function(*a1) - function(*a2); else *epsilon = function(*a2) - function(*a1); if(function(*a1) * function(*a2) < 0.0 && *epsilon >= 0.00001) { fprintf(bisection, "%.4f %.4f %.4f %.4f %.4f\n", *a1, *a2, function(*a1), function(*a1), *epsilon); attractor(a1, a2, epsilon); } else { *a2 = a2_copia; *a1 = a3; if(function(*a1) - function(*a2) > 0) *epsilon = function(*a1) - function(*a2); else *epsilon = function(*a2) - function(*a1); if(function(*a1) * function(*a2) < 0.0 && *epsilon >= 0.00001) { fprintf(bisection, "%.4f %.4f %.4f %.4f %.4f\n", *a1, *a2, function(*a1), function(*a1), *epsilon); attractor(a1, a2, epsilon); } } } fa1 = function(*a1); fa2 = function(*a2); if(function(*a1) - function(*a2) > 0.0) *epsilon = function(*a1) - function(*a2); else *epsilon = function(*a2) - function(*a1); fprintf(bisection, "%.4f %.4f %.4f %.4f %.4f\n", a1, a2, fa1, fa2, epsilon); } double function(double a) { double fa; fa = (a * cosh(h / (2 * a))) - R; return fa; } int main() { double a1, a2, fa1, fa2, epsilon; a1 = 0.1; a2 = 0.5; fa1 = function(a1); fa2 = function(a2); if(fa1 - fa2 > 0.0) epsilon = fa1 - fa2; else epsilon = fa2 - fa1; if(epsilon >= 0.00001) { fa1 = function(a1); fa2 = function(a2); attractor(&a1, &a2, &epsilon); fa1 = function(a1); fa2 = function(a2); if(fa1 - fa2 > 0.0) epsilon = fa1 - fa2; else epsilon = fa2 - fa1; } if(epsilon < 0.0001) printf("Vanish at %f", a2); else printf("ERROR"); return 0; } Thanks anyway and sorry if this question is not suitable.

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  • Extension method question. Why do I need to use someObj = someObj.somemethod();

    - by Kettenbach
    Hi All, I have a simple extension method that I would like to use to add an item to an array of items. public static T[] addElement<T>(this T[] array, T elementToAdd) { var list = new List<T>(array) {elementToAdd}; return list.ToArray(); } this works ok, but when I use it, I am having to set the array equal to the return value. I see that I am returning an Array. I likely want this method to be void, but I would like the item added. Does anyone have any ideas on what I need to do , to make this work the way I am wanting? Instead of someArray = someArray.addElement(item), I just want to do someArray.addElement(item) and then someArray be ready to go. What am I missing here? Thanks, ~ck in San Diego

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  • No Method Error Undefined method 'save' for nil:NilClass

    - by BennyB
    I'm getting this error when i try to create a "Lecture" via my Lecture controller's create method. This used to work but i went on to work on other parts of the app & then of course i come back & something is now throwing this error when a user tries to create a Lecture in my app. I'm sure its something small i'm just overlooking (been at it a while & probably need to take a break)...but I'd appreciate if someone could let me know why this is happening...let me know if i need to post anything else...thx! The error I get NoMethodError in LecturesController#create undefined method `save' for nil:NilClass Rails.root: /Users/name/Sites/rails_projects/app_name Application Trace | Framework Trace | Full Trace app/controllers/lectures_controller.rb:13:in `create' My view to create a new Lecture views/lectures/new.html.erb <% provide(:title, 'Start a Lecture') %> <div class="container"> <div class="content-wrapper"> <h1>Create a Lecture</h1> <div class="row"> <div class="span 6 offset3"> <%= form_for(@lecture) do |f| %> <%= render 'shared/error_messages', :object => f.object %> <div class="field"> <%= f.text_field :title, :placeholder => "What will this Lecture be named?" %> <%= f.text_area :content, :placeholder => "Describe this Lecture & what will be learned..." %> </div> <%= f.submit "Create this Lecture", :class => "btn btn-large btn-primary" %> <% end %> </div> </div> </div> </div> Then my controller where its saying the error is coming from controllers/lectures_controller.rb class LecturesController < ApplicationController before_filter :signed_in_user, :only => [:create, :destroy] before_filter :correct_user, :only => :destroy def index end def new @lecture = current_user.lectures.build if signed_in? end def create if @lecture.save flash[:success] = "Lecture created!" redirect_to @lecture else @activity_items = [ ] render 'new' end end def show @lecture = Lecture.find(params[:id]) end def destroy @lecture.destroy redirect_to root_path end private def correct_user @lecture = current_user.lectures.find_by_id(params[:id]) redirect_to root_path if @lecture.nil? end

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  • How to use a method with more than one parameters to create custom buttons

    - by iphonix
    I am repeating my codes few times to create custom buttons, I am trying to create a method and create all my required buttons just by called that method and using two parameters, btnTitle and btnAction. My Codes for the method -(void) addnewButton:(NSString *) btnTitle withAction:UIAction btnAction; { // Add a custom edit navigation button editButton = [[[UIBarButtonItem alloc] initWithTitle:NSLocalizedString((btnTitle), @"") style:UIBarButtonItemStyleBordered target:self action:@selector(btnAction)] autorelease]; self.navigationItem.rightBarButtonItem = editButton; } Now how shall I call this method to create a button?

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  • Using ms: xpath functions inside XPathExpression

    - by Filini
    I am trying to use Microsoft XPath Extension Functions (such as ms:string-compare http://msdn.microsoft.com/en-us/library/ms256114.aspx) inside an XPathExpression object. These functions are extensions inside the MSXML library, and if I use them in an XslCompiledTransform (simply adding the "ms" namespace) they work like a charm: var xsl = @" <?xml version=""1.0"" encoding=""UTF-8""?> <xsl:stylesheet version=""2.0"" xmlns:xsl=""http://www.w3.org/1999/XSL/Transform"" xmlns:xs=""http://www.w3.org/2001/XMLSchema"" xmlns:fn=""http://www.w3.org/2005/xpath-functions"" xmlns:ms=""urn:schemas-microsoft-com:xslt""> <xsl:output method=""xml"" version=""1.0"" encoding=""UTF-8"" indent=""yes""/> <xsl:template match=""/Data""> <xsl:element name=""Result""> <xsl:value-of select=""ms:string-compare(@timeout1, @timeout2)""/> </xsl:element> </xsl:template> </xsl:stylesheet>"; var xslDocument = new XmlDocument(); xslDocument.LoadXml(xsl); var transform = new XslCompiledTransform(); transform.Load(xslDocument); Then I tried using them in an XPathExpression: XPathNavigator nav = document.DocumentElement.CreateNavigator(); XPathExpression expr = nav.Compile("ms:string-compare(/Data/@timeout1, /Data/@timeout2)"); XmlNamespaceManager manager = new XmlNamespaceManager(document.NameTable); manager.AddNamespace("ms", "urn:schemas-microsoft-com:xslt"); expr.SetContext(manager); nav.Evaluate(expr); But I get an exception "XsltContext is needed for this query because of an unknown function". XsltContext is a specific XmlNamespaceManager, but I don't know if it's possible to instantiate it without an actual XslCompiledTransform (it's abstract) and use it as my expression context. Is there any way to do this (or any other way to use ms: extensions inside an XPathExpression)?

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  • Java method help

    - by dalton conley
    Ok, so I'm working on a project for a class I'm taking.. simple music library. Now I'm having some issues, the main issue is I'm getting "non-static method cannot be referenced from a static context" Here is a function I have public void addSong() { Scanner scan = new Scanner(System.in); Song temp = new Song(); int index = countFileLines(Main.databaseFile); index = index + 2; temp.index = index; System.out.print("Enter the artist name: "); temp.artist.append(scan.next()); } Now thats in a class file called LibraryFunctions. So I can access it with LibraryFunctions.addSong(); Now I'm trying to run this in my main java file and its giving me the error, I know why the error is happening, but what do I do about it? If I make addSong() a static function then it throws errors at me with the Song temp = new Song() being static. Kind of ironic. Much help is appreciated on this!

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  • loading method based on URL

    - by steeped
    I am trying to build a small mvc-based application. How do I call a method in a class based on a query string? For example, the $_GET query string is being set as load_master_form http://www.domain.com/settings/load_master_form And to call the method within the settings class, I am doing: function __construct(){ $this->{$_GET['method']}(); } But obviously that doesn't work - it just isn't possible to load a method like that. So how would it be done?

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  • Process every pair in a sequence

    - by Henry Jackson
    I'm looking for a concise way to process every (unordered) pair of elements in a sequence in .NET. I know I can do it with nested foreach loops, but I was looking for something a little more readable. I was imagining something like a modified Any() extension method: IEnumerable<Transaction> transactions = ... if (transactions.AnyPair( (first, second) => first.UniqueID == second.UniqueID)) throw ... Or maybe a foreach-style one: IEnumerable<JigsawPiece> pieces = ... pieces.ForEachPair( (first, second) => { TryFit(first, second); }); This question has been asked for other languages (e.g. see http://stackoverflow.com/questions/942543/operation-on-every-pair-of-element-in-a-list), but I'm looking for a .NET solution.

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  • LINQ .Cast() extension method fails but (type)object works.

    - by Ben Robinson
    To convert between some LINQ to SQL objects and DTOs we have created explicit cast operators on the DTOs. That way we can do the following: DTOType MyDTO = (LinqToSQLType)MyLinq2SQLObj; This works well. However when you try to cast using the LINQ .Cast() extension method it trows an invalid cast exception saying cannot cast type Linq2SQLType to type DTOType. i.e. the below does not work List<DTO.Name> Names = dbContact.tNames.Cast<DTO.Name>() .ToList(); But the below works fine: DAL.tName MyDalName = new DAL.tName(); DTO.Name MyDTOName = (DTO.Name)MyDalName; and the below also works fine List<DTO.Name> Names = dbContact.tNames.Select(name => (DTO.Name)name) .ToList(); Why does the .Cast() extension method throw an invalid cast exception? I have used the .Cast() extension method in this way many times in the past and when you are casting something like a base type to a derived type it works fine, but falls over when the object has an explicit cast operator.

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  • Error message in XSLT with C# extension function

    - by iHeartGreek
    Hi! I am received the following error while trying to implement a C# extension function in XSLT. Extension function parameters or return values which have CLR type 'Char[]' are not supported.** code: <xsl:variable name="stringList"> <xsl:value-of select="extension:GetList('AAA BBB CCC', ' ')"/> </xsl:variable> <msxsl:script language="C#" implements-prefix="extension"> <![CDATA[ public string[] GetList(string str, char[] delimiter) { ... ... return str.Split(delimiter, StringSplitOptions.None); } ]]> </msxsl:script> Can someone explain this error message and how to get past it? Thanks!

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  • Trouble calling a method from an external class

    - by Bradley Hobbs
    Here is my employee database program: import java.util.*; import java.io.*; import java.io.File; import java.io.FileReader; import java.util.ArrayList; public class P { //Instance Variables private static String empName; private static String wage; private static double wages; private static double salary; private static double numHours; private static double increase; // static ArrayList<String> ARempName = new ArrayList<String>(); // static ArrayList<Double> ARwages = new ArrayList<Double>(); // static ArrayList<Double> ARsalary = new ArrayList<Double>(); static ArrayList<Employee> emp = new ArrayList<Employee>(); public static void main(String[] args) throws Exception { clearScreen(); printMenu(); question(); exit(); } public static void printArrayList(ArrayList<Employee> emp) { for (int i = 0; i < emp.size(); i++){ System.out.println(emp.get(i)); } } public static void clearScreen() { System.out.println("\u001b[H\u001b[2J"); } private static void exit() { System.exit(0); } private static void printMenu() { System.out.println("\t------------------------------------"); System.out.println("\t|Commands: n - New employee |"); System.out.println("\t| c - Compute paychecks |"); System.out.println("\t| r - Raise wages |"); System.out.println("\t| p - Print records |"); System.out.println("\t| d - Download data |"); System.out.println("\t| u - Upload data |"); System.out.println("\t| q - Quit |"); System.out.println("\t------------------------------------"); System.out.println(""); } public static void question() { System.out.print("Enter command: "); Scanner q = new Scanner(System.in); String input = q.nextLine(); input.replaceAll("\\s","").toLowerCase(); boolean valid = (input.equals("n") || input.equals("c") || input.equals("r") || input.equals("p") || input.equals("d") || input.equals("u") || input.equals("q")); if (!valid){ System.out.println("Command was not recognized; please try again."); printMenu(); question(); } else if (input.equals("n")){ System.out.print("Enter the name of new employee: "); Scanner stdin = new Scanner(System.in); empName = stdin.nextLine(); System.out.print("Hourly (h) or salaried (s): "); Scanner stdin2 = new Scanner(System.in); wage = stdin2.nextLine(); wage.replaceAll("\\s","").toLowerCase(); if (!(wage.equals("h") || wage.equals("s"))){ System.out.println("Input was not h or s; please try again"); } else if (wage.equals("h")){ System.out.print("Enter hourly wage: "); Scanner stdin4 = new Scanner(System.in); wages = stdin4.nextDouble(); Employee emp1 = new HourlyEmployee(empName, wages); emp.add(emp1); printMenu(); question();} else if (wage.equals("s")){ System.out.print("Enter annual salary: "); Scanner stdin5 = new Scanner(System.in); salary = stdin5.nextDouble(); Employee emp1 = new SalariedEmployee(empName, salary); printMenu(); question();}} else if (input.equals("c")){ for (int i = 0; i < emp.size(); i++){ System.out.println("Enter number of hours worked by " + emp.get(i) + ":"); } Scanner stdin = new Scanner(System.in); numHours = stdin.nextInt(); System.out.println("Pay: " + emp1.computePay(numHours)); System.out.print("Enter number of hours worked by " + empName); Scanner stdin2 = new Scanner(System.in); numHours = stdin2.nextInt(); System.out.println("Pay: " + emp1.computePay(numHours)); printMenu(); question();} else if (input.equals("r")){ System.out.print("Enter percentage increase: "); Scanner stdin = new Scanner(System.in); increase = stdin.nextDouble(); System.out.println("\nNew Wages"); System.out.println("---------"); // System.out.println(Employee.toString()); printMenu(); question(); } else if (input.equals("p")){ printArrayList(emp); printMenu(); question(); } else if (input.equals("q")){ exit(); } } } Here is one of the class files: public abstract class Employee { private String name; private double wage; protected Employee(String name, double wage){ this.name = name; this.wage = wage; } public String getName() { return name; } public double getWage() { return wage; } public void setName(String name) { this.name = name; } public void setWage(double wage) { this.wage = wage; } public void percent(double wage, double percent) { wage *= percent; } } And here are the errors: P.java:108: cannot find symbol symbol : variable emp1 location: class P System.out.println("Pay: " + emp1.computePay(numHours)); ^ P.java:112: cannot find symbol symbol : variable emp1 location: class P System.out.println("Pay: " + emp1.computePay(numHours)); ^ 2 errors I'm trying to the get paycheck to print out but i'm having trouble with how to call the method. It should take the user inputed numHours and calculate it then print on the paycheck for each employee. Thanks!

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  • Javascript - cannot make static reference to non-static function ....

    - by Ankur
    I am making a reference to the Javascript function splice() on an array and I get the error: "Cannot make a static reference to the non-static function splice()" What's going on - how is this a static reference, aren't I referencing an instance of an Array class and its method - how is that static? $(document).ready( function() { var queryPreds = new Array(); var queryObjs = new Array(); function remFromQuery(predicate) { for(var i=0; i<arrayName.length;i++ ) { if(queryPreds[i]==predicate) queryPreds.splice(i,1); queryObjs.splice(i,1); } } }

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  • Why can't you call a non-static method from a static method?

    - by VoodooChild
    I have a static method [Method1] in my class, which calls another method [Method2] in the same class and is not a static method. But this is a no-no. I get this error: An object reference is required for the non-static field, method, or property "ClassName.MethodName()" Can someone please briefly describe why? including other things that might be related to this.

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  • Extension method not working if I set controller property in Action, works in OnExecuting

    - by Blankman
    I have a class MyController that inherits from Controller, so all my controllers inherit from MyController. I have a property in MyController: public class MyController : Controller { public string SomeProperty {get;set;} } if I set this property in MyController's OnExecuting method, my HtmlHelper extension method works fine: public static string SomeExtension(this HtmlHelper htmlHelper) { StringBuilder sb = new StringBuilder(); string result = ""; var controller = htmlHelper.ViewContext.Controller as MyController; if (controller != null) { result = controller.SomeProperty; } return result; } it doesn't work if I set 'SomeProperty' in my controllers action method. I guess because I am doing 'as MyController' in the extension method? is there a way for it to work in both situations? I am using the value of SomeProperty to be outputted on my view pages.

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  • C# Extension Method for String Data Type

    - by Jimbo
    My web application deals with strings that need to be converted to numbers alot - users often put commas, currency symbols etc. in these fields so what I want to do is create a string extension method that cleans the field up and converts it to a decimal. For example: decimal myNumber = "$1,250.85".ToDecimal(); Can anyone help with this? Thanks!

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  • Can fields of the class and arguments of the method interfere?

    - by Roman
    I have a class with a fields called "a". In the class I have a method and in the list of arguments of this method I also have "a". So, which "a" I will see inside of the method? Will it be the field or it will be the argument of the method? public class myClass { private String a; // Method which sets the value of the field "a". public void setA(String a) { a = a; } } By the way, there is a similar situation. A method has some local (for method) variables whose names coincide with the names of the fields. What will the "see" the method if I refer to such a method-local variable inside the method (the field or the local variable)?

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  • using empty on inaccessible object with __isset and __get

    - by David
    <?php class Magic_Methods { protected $meta; public function __construct() { $this->meta = (object) array( 'test' => 1 ); } public function __isset($name) { echo "pass isset {$name} \n"; return isset($this->$name); } public function __get($name) { echo "pass get {$name} \n"; return $this->$name; } } $mm = new Magic_Methods(); $meta = empty($mm->meta->notExisting); var_dump($meta); echo "||\n"; $meta = empty($mm->meta); var_dump($meta); The snippet above does not work as expected for me. Why would the first empty() ommit the __isset? I get this: pass get meta bool(true) || pass isset meta pass get meta bool(false) I would expected identical results or another pass at the __isset, but not a direct call to __get. Or am I missing something here?

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  • c# creating a database query METHOD

    - by Sinaesthetic
    I'm not sure if im delluded but what I would like to do is create a method that will return the results of a query, so that i can reuse the connection code. As i understand it, a query returns an object but how do i pass that object back? I want to send the query into the method as a string argument, and have it return the results so that I can use them. Here's what i have which was a stab in the dark, it obviously doesn't work. This example is me trying to populate a listbox with the results of a query; the sheet name is Employees and the field/column is name. The error i get is "Complex DataBinding accepts as a data source either an IList or an IListSource.". any ideas? public Form1() { InitializeComponent(); openFileDialog1.ShowDialog(); openedFile = openFileDialog1.FileName; lbxEmployeeNames.DataSource = Query("Select [name] FROM [Employees$]"); } public object Query(string sql) { System.Data.OleDb.OleDbConnection MyConnection; System.Data.OleDb.OleDbCommand myCommand = new System.Data.OleDb.OleDbCommand(); string connectionPath; //build connection string connectionPath = "provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + openedFile + "';Extended Properties=Excel 8.0;"; MyConnection = new System.Data.OleDb.OleDbConnection(connectionPath); MyConnection.Open(); myCommand.Connection = MyConnection; myCommand.CommandText = sql; return myCommand.ExecuteNonQuery(); }

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  • Cannot make a static reference to the non-static type MyRunnable

    - by kaiwii ho
    Here is the whole code : import java.util.ArrayList; public class Test{ ThreadLocal<ArrayList<E>>arraylist=new ThreadLocal<ArrayList<E>>(){ @Override protected ArrayList<E> initialValue() { // TODO Auto-generated method stub //return super.initialValue(); ArrayList<E>arraylist=new ArrayList<E>(); for(int i=0;i<=20;i++) arraylist.add((E) new Integer(i)); return arraylist; } }; class MyRunnable implements Runnable{ private Test mytest; public MyRunnable(Test test){ mytest=test; // TODO Auto-generated constructor stub } @Override public void run() { System.out.println("before"+mytest.arraylist.toString()); ArrayList<E>myarraylist=(ArrayList<E>) mytest.arraylist.get(); myarraylist.add((E) new Double(Math.random())); mytest.arraylist.set(myarraylist); System.out.println("after"+mytest.arraylist.toString()); } // TODO Auto-generated method stub } public static void main(String[] args){ Test test=new Test<Double>(); System.out.println(test.arraylist.toString()); new Thread(new MyRunnable(test)).start(); new Thread(new MyRunnable(test)).start(); System.out.println(arraylist.toString()); } } my questions are: 1\ why the new Thread(new MyRunnable(test)).start(); cause the error: Cannot make a static reference to the non-static type MyRunnable ? 2\ what is the static reference refer to right here? thx in advanced

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  • Whats wrong with this method?

    - by David
    Here's the method: public static String CPUcolor () { System.out.println ("What color am I?") ; String s = getIns() ; System.out.println ("are you sure I'm "+s+"? (Y/N)") ; String a = getIns() ; while (!((a.equals ("y")) || (a.equals ("Y")) || (a.equals ("n")) || (a.equals ("N")))) { System.out.println ("try again") ; a = getIns () ; } if (a.equals ("n") || a.equals("N")) {CPUcolor() ;} System.out.println ("I am "+s) ; return s ; } here is a possible output of this method (y's and n's are user inputs): What color am I? red are you sure I'm red? (Y/N) N What color am I? blue are you sure I'm blue? (Y/N) N What color am I? Yellow are you sure I'm Yellow? (Y/N) y I am Yellow I am blue I am red Why is it that the line's "I am blue" and "I am Blue" printed? Why are they printed in reverse order with red, the first entered, printed last?

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  • Does iPhone SDK Objective C support functions inside of functions?

    - by Moshe
    I know that javascript, for example supports functions inside of functions, like so: function doSomething(){ function doAnothingThing(){ //this function is redefined every time doSomething() is called and only exists inside doSomething() } //you can also stick it inside of conditions if(yes){ function doSomethingElse(){ //this function only exists if yes is true } } } Does objective-c support this? Theoretical example: -(void) doSomething:(id) sender{ -(void) respondToEvent: (id) sender{ //theoretically? ... please? } } BONUS: What is the proper term for a "local" function?

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  • How do I show and position an Image initialized in the codebehind on my page?

    - by Andreas Strandfelt
    Hello. I have created a simple method to check if an image has been approved and finally returns it as an control. But how do i call and show it on the page? I've tried something like this in the aspx-file: <% SendImage("DKBygMiniLogo.gif", "True"); %> Here is the simple method: protected Image SendImage(object Image, object Approved) { bool approved = Convert.ToBoolean(Approved); Image img = new Image(); if (approved) { img.ImageUrl = "~/images/Ads/" + Image.ToString(); img.Visible = true; } else { img.ImageUrl = "~/images/Ads/" + Image.ToString(); img.Visible = false; } return img; } How do I actually show the image?

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  • How do I avoid boxing/unboxing when extending System.Object?

    - by Robert H.
    I'm working on an extension method that's only applicable to reference types. I think, however, it's currently boxing and unboxing the the value. How can I avoid this? namespace System { public static class SystemExtensions { public static TResult GetOrDefaultIfNull<T, TResult>(this T obj, Func<T, TResult> getValue, TResult defaultValue) { if (obj == null) return defaultValue; return getValue(obj); } } } Example usage: public class Foo { public int Bar { get; set; } } In some method: Foo aFooObject = new Foo { Bar = 1 }; Foo nullReference = null; Console.WriteLine(aFooObject.GetOrDefaultIfNull((o) => o.Bar, 0)); // results: 1 Console.WriteLine(nullReference.GetOrDefaultIfNull((o) => o.Bar, 0)); // results: 0

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