Question

I am trying to Serialize the content of some text into an XML file (performed when a user saves their selections), and then will later deserialize it (when the user chooses to display their saved selection).

I have been following the following tutorial on serialization.

I have also tried to do this via LINQ to XML but was either getting namespace errors, or the tool returned no errors, but did not work (with the same problem as described below).

The problem I am having is that my code is not returning any errors, but the function is not working (I have a label control that allows me to see that the ‘catch’ is being returned). I am building the tool in Expression Blend, using C#.

Here is my SaveSelection.cs Class

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Xml.Serialization;
using System.Xml;

namespace DYH
{
public class SaveSelections
{
    [XmlAttribute("Title")]
    public string Title
    { get; set; }

    [XmlElement("Roof")]
    public string RoofSelection
    { get; set; }

    [XmlElement("Cladding")]
    public string CladdingSelection
    { get; set; }

    [XmlElement("MixedCladding")]
    public string MixedCladdingSelection
    { get; set; }

    [XmlElement("FAJ")]
    public string FAJSelection
    { get; set; }

    [XmlElement("GarageDoor")]
    public string GarageDoorSelection
    { get; set; }

    [XmlElement("FrontDoor")]
    public string FrontDoorSelection
    { get; set; }
}
}

Here is my C# code

// Save Selection Button
        private void Button_SaveSelection_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
        {   
            try
            {
                // Save selections into the SavedSelections.xml doc
                SaveSelections userselection = new SaveSelections();
                userselection.Title = TextBox_SaveSelection.Text;
                userselection.RoofSelection = Button_Roof_Select.Text;
                userselection.CladdingSelection = Button_Cladding_Select.Text;
                userselection.MixedCladdingSelection = Button_MixedCladding_Select.Text;
                userselection.FAJSelection = Button_FAJ_Select.Text;
                userselection.GarageDoorSelection = Button_GarageDoor_Select.Text;
                userselection.FrontDoorSelection = Button_FrontDoor_Select.Text;

                SerializeToXML(userselection);

//              XDocument xmlSaveSelections = XDocument.Load("../SavedSelections.xml");
//          
//              XElement newSelection = new XElement("Selection", //xmlSaveSelections.Element("Selections").Add(
//                      //new XElement("Selection",
//                      new XElement("Title", TextBox_SaveSelection.Text),
//                      new XElement("RoofSelection", Button_Roof_Select.Text),
//                      new XElement("CladdingSelection", Button_Cladding_Select.Text),
//                      new XElement("MixedCladdingSelection", Button_MixedCladding_Select.Text),
//                      new XElement("FAJSelection", Button_FAJ_Select.Text),
//                      new XElement("GarageDoorSelection", Button_GarageDoor_Select.Text),
//                      new XElement("FrontDoorSelection", Button_FrontDoor_Select.Text));
//              
////                xmlSaveSelections.Add(newSelection);
////                xmlSaveSelections.Save("../SavedSelections.xml");

                SelectionLabel.Text = "Your selection has been saved as " + "'" + TextBox_SaveSelection.Text + "'. We suggest you write down the name of your selection.";
            }
            catch(Exception ex)
            {
                            throw ex;
                SelectionLabel.Text = "There was a problem saving your selection. Please try again shortly.";
            }
        }

        // Saves SaveSelection.cs to XML file SavedSelections.xml
        static public void SerializeToXML(SaveSelections selection)
        {
            XmlSerializer serializer = new XmlSerializer(typeof(SaveSelections));
            TextWriter textWriter = new StreamWriter(@"/SavedSelections.xml");
            serializer.Serialize(textWriter, selection);
            textWriter.Close();
        }

I have left evidence of one of my previous attempts commented out so you can see a previous format I tried.

My issue is that when I try to use the tool, the SelectionLabel.Text returns “There was a problem saving your selection. Please try again shortly.” so I know that the code is returning the catch and not executing the ‘try’.

Any help??

Edit 18/6/2012: The below code was the code that worked as per correct answer to question.

public void Button_SaveSelection_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
    {
        string roofSelection = TextBox_SaveSelection.Text + "_RoofSelection";
        string claddingSelection = TextBox_SaveSelection.Text + "_CladdingSelection";
        string mixedCladdingSelection = TextBox_SaveSelection.Text + "_MixedCladdingSelection";
        string fajSelection = TextBox_SaveSelection.Text + "_FAJSelection";
        string garageDoorSelection = TextBox_SaveSelection.Text + "_GarageDoorSelection";
        string frontDoorSelection = TextBox_SaveSelection.Text + "_FrontDoorSelection";

        try
        {
            using (var store = IsolatedStorageFile.GetUserStoreForApplication())
            {
                // Gives us 6Mb of storage space in IsoStore
                Int64 isoSpaceNeeded = 1048576 * 6;
                Int64 currentIsoSpace = store.AvailableFreeSpace;

                // If space needed is greater than (>) space available, increase space
                if (isoSpaceNeeded > currentIsoSpace)
                {
                    // If user accepts space increase
                    if (store.IncreaseQuotaTo(currentIsoSpace + isoSpaceNeeded))
                    {
                        IsolatedStorageFileStream file = store.CreateFile("SavedSelections.txt");
                        file.Close();

                        // Stream writer to populate information in
                        using (StreamWriter sw = new StreamWriter(store.OpenFile("SavedSelections.txt", FileMode.Open, FileAccess.Write)))
                        {
                            appSettings.Add(roofSelection, Button_Roof_Select.Text);
                            sw.WriteLine(roofSelection);
                            appSettings.Add(claddingSelection, Button_Cladding_Select.Text);
                            sw.WriteLine(claddingSelection);
                            appSettings.Add(mixedCladdingSelection, Button_MixedCladding_Select.Text);
                            sw.WriteLine(mixedCladdingSelection);
                            appSettings.Add(fajSelection, Button_FAJ_Select.Text);
                            sw.WriteLine(fajSelection);
                            appSettings.Add(garageDoorSelection, Button_GarageDoor_Select.Text);
                            sw.WriteLine(garageDoorSelection);
                            appSettings.Add(frontDoorSelection, Button_FrontDoor_Select.Text);
                            sw.WriteLine(frontDoorSelection);
                        }

                        SelectionLabel.Text = "Your selection has been saved as " + "'" + TextBox_SaveSelection.Text + "'. We suggest you write down the name of your selection.";
                    }
                }
            }

            SelectionLabel.Text = "Your selection has been saved as " + "'" + TextBox_SaveSelection.Text + "'. We suggest you write down the name of your selection.";
        }
        catch //(Exception ex)
        {
            //throw ex;
            SelectionLabel.Text = "There was a problem saving your selection. Please try again shortly.";
        }
    }

Answer 1

It looks like your issue is because you’re trying to a file, but that file did not come from a FileSaveDialog initiated by a user action. You’re running into a security feature of Silverlight where you’re not allowed access to the local file system. Instead, try writing to IsolatedStorage. However, be aware that end users can completely (as well as selectively) disable application storage so you’ll need to handle those exceptions as well.

Here’s a quick article on how to use IsolatedStorage.