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POCannot change labels using listbox selected item via class
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  1. POCannot change labels using listbox selected item via class
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    copied!<p>I have a listbox which holds a name of a tag from and xml file, there are other tags which are also held in a class but when I try to click on a value inside the listbox to set my label text to what the value is inside of the class I get the following error: "InvalidCastException was unhandled. Unable to cast object of type 'System.String' to type 'Coursework1.modules'." Heres the code, this is inside the listbox event for when the index has changed.</p> <pre><code>for (int i = 0; i &lt; selectionBox.Items.Count; i++) { if (selectionBox.GetSelected(i) == true) { infoLabel.Text = ((modules)selectionBox.Items[i]).mInfo; lectureSlotLabel.Text = ((modules)selectionBox.Items[i]).mLSlot; tutorialLabel.Text = ((modules)selectionBox.Items[i]).mTSlot; prerequisiteLabel.Text = ((modules)selectionBox.Items[i]).mPreReq; codeLabel.Text = ((modules)selectionBox.Items[i]).mCode; nameLabel.Text =((modules)selectionBox.Items[i]).mName; } } </code></pre> <p>//Selection box creation</p> <pre><code> String workingDir = Directory.GetCurrentDirectory(); XmlTextReader textReader = new XmlTextReader(workingDir + @"\XML.xml"); textReader.Read(); XmlNodeType type; while (textReader.Read()) { textReader.MoveToElement(); type = textReader.NodeType; if (type == XmlNodeType.Element) { //if (textReader.Name == "Code") //{ // module.Add(new modules(textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString(), // textReader.ReadElementContentAsString())); //} if (textReader.Name == "Code") { textReader.Read(); code = textReader.Value; Console.WriteLine(code); } if (textReader.Name == "Name") { textReader.Read(); name = textReader.Value; //selectionBox.Items.Add(name); Console.WriteLine(name); } if (textReader.Name == "Semester") { textReader.Read(); semester = textReader.Value; Console.WriteLine(semester); } if (textReader.Name == "Prerequisite") { textReader.Read(); preReq = textReader.Value; Console.WriteLine(code); } if (textReader.Name == "LectureSlot") { textReader.Read(); lSlot = textReader.Value; Console.WriteLine(lSlot); } if (textReader.Name == "TutorialSlot") { textReader.Read(); tSlot = textReader.Value; Console.WriteLine(tSlot); } if (textReader.Name == "Info") { textReader.Read(); info = textReader.Value; Console.WriteLine(info); module.Add(new Modules(code, name, semester, tSlot, lSlot, info, preReq)); } } //Console.WriteLine(module); } foreach (object o in module) { Modules m = (Modules)o; //String hold = m.mName; selectionBox.Items.Add(m.mName); } textReader.Close(); </code></pre> <p>//Label text being used</p> <pre><code>var xmlFile = XDocument.Load(xmlDirectory + @"\XML.xml"); //Finds the XML file again and looks for the Name tag var mName = from directory in xmlFile.Descendants("Name") where directory.Value == (String)selectionBox.SelectedItem select directory.Parent.Element("Name").Value; //in the mName we search the directory for the Name tag and after we search //for the selected item of the list in the directory after that we look for //the "Name" element in the directory and that gets the name value and saves it to //mName foreach (var item in mName) { //use the loop to make it dynamic as when the selected item changes so does, //the moduleName label nameLabel.Text = item.ToString(); } </code></pre>
 

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