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POAssistance required with delegates example
 

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    <p>Been trying to wrap my head around delegates, but always seem to hit a brick wall when it comes to it sinking in.</p> <p>I've tried to make my own example to help me understand, after reading an article about delegates -> <a href="http://www.codeproject.com/Articles/71154/C-Delegates-101-A-Practical-Example" rel="nofollow">http://www.codeproject.com/Articles/71154/C-Delegates-101-A-Practical-Example</a> but so far have been unsucessful. The following code produces an error about this line: 'doneExecuting = FunctionListToRun(MainOfWindows);' = Unassigned local variable</p> <p>Can someone tell me if I'm close and what I'm doing wrong?</p> <p>(I've also included the UI code on pastebin in case it helps -> <a href="http://pastebin.com/D2BVZJXc" rel="nofollow">http://pastebin.com/D2BVZJXc</a>)</p> <pre><code>public partial class MainWindow : Window { public delegate bool FunctionToCall(MainWindow windowInstance); public MainWindow() { InitializeComponent(); addMethodNames(); } private void addMethodNames() { ListBoxItem lbi1 = new ListBoxItem(); lbi1.Content = "Introduction"; lbi1.Name = "get" + lbi1.Content; listMethods.Items.Add(lbi1); ListBoxItem lbi2 = new ListBoxItem(); lbi1.Content = "Greeting"; lbi2.Name = "get" + lbi2.Content; listMethods.Items.Add(lbi2); ListBoxItem lbi3 = new ListBoxItem(); lbi3.Content = "Story"; lbi3.Name = "get" + lbi3.Content; listMethods.Items.Add(lbi3); ListBoxItem lbi4 = new ListBoxItem(); lbi4.Content = "MyName"; lbi4.Name = "get" + lbi4.Content; listMethods.Items.Add(lbi4); ListBoxItem lbi6 = new ListBoxItem(); lbi6.Content = "Conclusion"; lbi6.Name = "get" + lbi6.Content; listMethods.Items.Add(lbi6); } private void btnAddAction_Click(object sender, RoutedEventArgs e) { ListBoxItem lbi = (ListBoxItem)listMethods.Items[listMethods.SelectedIndex]; listMethods.Items.Remove(lbi); listActions.Items.Add(lbi); } private void btnRemoveAction_Click(object sender, RoutedEventArgs e) { listActions.Items.RemoveAt(listActions.SelectedIndex); } private void btnRun_Click(object sender, RoutedEventArgs e) { bool doneExecuting = false; FunctionToCall FunctionListToRun; foreach (ListBoxItem methodName in listActions.Items) { Conclusion conc = new Conclusion(); switch (methodName.Content.ToString()) { case "Introduction": Introduction intro = new Introduction(); FunctionListToRun = intro.getIntroduction; break; case "Greeting": Greeting greet = new Greeting(); FunctionListToRun = greet.getGreeting; break; case "Story": Story story = new Story(); FunctionListToRun = story.getStory; break; case "MyName": MyName name = new MyName(); FunctionListToRun = name.getName; break; case "Conclusion": FunctionListToRun = conc.getConclusion; break; default: FunctionListToRun = conc.getConclusion; break; } } doneExecuting = FunctionListToRun(MainOfWindows); } } class Introduction { public bool getIntroduction(MainWindow windowInstance) { windowInstance.txtResult.Text += " Hello there!"; return true; } } class Greeting { public bool getGreeting(MainWindow windowInstance) { windowInstance.txtResult.Text += " How are you today?"; return true; } } class Story { public bool getStory(MainWindow windowInstance) { windowInstance.txtResult.Text += " I once met a goat and his name was billy, and he lived on a plain that was very hilly."; return true; } } class MyName { public bool getName(MainWindow windowInstance) { windowInstance.txtResult.Text += " My name is too infinity!"; return true; } } class Conclusion { public bool getConclusion(MainWindow windowInstance) { windowInstance.txtResult.Text += " That is all, goodbye!"; return true; } } </code></pre>
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    1. CODude, I have no idea what you're talking about, but your code is terrible. You must not create or manipulate UI elements in code in WPF.
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      1. USFederico Berasategui
    2. COI would suggest reading this article it gives examples of delegate as well as using Action<T> and a few other cool things to try.. http://msdn.microsoft.com/en-us/library/018hxwa8.aspx
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    3. CO_"You must not create or manipulate UI elements in code in WPF"_ Says who?
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      1. USChris Sinclair
 

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