There are multiple ways to store user data in winRT apps, one option for simple data is the LocalSettings, now the local settings can be simply used as a key value Collection, but that's rather boring, this is because you could in essence use a Resource dictionary for the same thing.
What's interesting about the LocalSettings date Container is that it can contain sub containers, so for example you could have multiple containers in the LocalSettings container that all have the same sub valuekey pairs, what i mean is you could have something like the following
- PersonOne
- FirstName
- LastName
- BirthDate
- PersonTwo
- FirstName
- LastName
- BirthDate
- PersonThree
- FirstName
- LastName
- BirthDate
- etc
ok lets look at an example
pretty straight forward app, now let's look at the xaml to make this happen
<Page
x:Class="pc.LocalSettings.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:pc.LocalSettings"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">
<Page.Resources>
<Style TargetType="TextBox">
<Setter Property="FontSize" Value="34"/>
</Style>
<Style TargetType="ComboBox">
<Setter Property="FontSize" Value="34"/>
</Style>
<Style TargetType="DatePicker">
<Setter Property="FontSize" Value="34"/>
</Style>
<Style TargetType="Button">
<Setter Property="FontSize" Value="34"/>
<Setter Property="Margin" Value="0 20 20 0"/>
</Style>
</Page.Resources>
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Grid.RowDefinitions>
<RowDefinition Height="100"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="100"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<TextBlock Grid.Column="1" Text="LocalSettings Example"
Style="{ThemeResource HeaderTextBlockStyle}"
VerticalAlignment="Center"/>
<StackPanel Grid.Column="1" Grid.Row="1" Margin="0 0 100 0">
<ComboBox x:Name="People_CB"/>
<TextBox x:Name="FirstName_TXT"
Header="First Name:"/>
<TextBox x:Name="LastName_TXT"
Header="Last Name:"/>
<DatePicker x:Name="BirthDate_DP"
Header="Date Picker:" />
<StackPanel Orientation="Horizontal">
<Button x:Name="Save_BTN" Content="Save"/>
<Button x:Name="Delete_BTN" Content="Delete"/>
</StackPanel>
</StackPanel>
</Grid>
</Page>
easy enough, i don't think anything warrants an explanation. so let's just jump into the code-behind
using System;
using System.Collections.Generic;
using Windows.Storage;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
namespace pc.LocalSettings
{
public sealed partial class MainPage : Page
{
public MainPage()
{
this.InitializeComponent();
//Get
the local settings
var localSettings = ApplicationData.Current.LocalSettings;
//use
the key of each of the containers as an item
//in our
people combo box
foreach (var fullName in localSettings.Containers.Keys)
this.People_CB.Items.Add(fullName);
//add
our event revievers
this.People_CB.SelectionChanged += People_CB_SelectionChanged;
this.Save_BTN.Click += Save_BTN_Click;
this.Delete_BTN.Click += Delete_BTN_Click;
}
//delete
a contianer from our local settings
void Delete_BTN_Click(object sender, RoutedEventArgs e)
{
//get
the key name from the combo box
var selectedPerson = People_CB.SelectedValue.ToString();
//get
our local settings container
var localSettings = ApplicationData.Current.LocalSettings;
//delete
the container with the specified key
localSettings.DeleteContainer(selectedPerson);
//remove
the corresponding key from the combo box
People_CB.Items.Remove(selectedPerson);
//clear
the input values
this.FirstName_TXT.Text = this.LastName_TXT.Text = String.Empty;
this.BirthDate_DP.Date = DateTimeOffset.Now;
}
//load
the data for a specific container
void People_CB_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
//prevent
error when deleting a container
if (e.AddedItems.Count == 0)
return;
//get
contaier key to load
var selectedPerson = e.AddedItems[0].ToString();
//get
local settings
var localSettings = ApplicationData.Current.LocalSettings;
//load
sub container with specified key
ApplicationDataContainer Person = localSettings.Containers[selectedPerson];
//populate
inputs with specified container values
this.FirstName_TXT.Text = Person.Values["firstName"].ToString();
this.LastName_TXT.Text = Person.Values["lastName"].ToString();
this.BirthDate_DP.Date = (DateTimeOffset)Person.Values["birthDate"];
}
void Save_BTN_Click(object sender, RoutedEventArgs e)
{
//get
values from input fields
var firstName = FirstName_TXT.Text;
var lastName = LastName_TXT.Text;
var birthDate = BirthDate_DP.Date;
//set
key to use
var fullName = String.Format("{0}
{1}", firstName, lastName);
//get
local settings
var localSettings = ApplicationData.Current.LocalSettings;
//get or
create the specified subcontaier
ApplicationDataContainer Person =
localSettings.CreateContainer(firstName, ApplicationDataCreateDisposition.Always);
//save
or update the subcontainers values
SaveContainerData(Person, "firstName",
firstName);
SaveContainerData(Person, "lastName",
lastName);
SaveContainerData(Person, "birthDate",
birthDate);
if (!this.People_CB.Items.Contains(firstName))
this.People_CB.Items.Add(firstName);
}
void SaveContainerData<T>(ApplicationDataContainer Container, string Key, T Value) {
//check
if contaier already has key, if so update it if not create it.
if (Container.Values.ContainsKey(Key))
Container.Values[Key] = Value;
else
Container.Values.Add(new KeyValuePair<string, object>(Key, Value));
}
}
}
the code-behind is pretty straight forward as well, the only thing really worth mentioning, is when creating a sub container that is
ApplicationDataContainer Person = localSettings.CreateContainer(firstName,
ApplicationDataCreateDisposition.Always);
you have two options
Always:loads the container if it exists or creates it if it doesn't
Existing:only loads contains that exist throws and exception if you try to create a new one.
