windows 8 app roaming storage with custom class

问题

I am learning programming in windows 8 with c#. I have worked through many tutorials (such as http://msdn.microsoft.com/en-us/library/windows/apps/hh986968.aspx) in the process and I am attempting to create a simple app showing data storage. All of the examples I have been able to find store only simple strings in roaming storage. Is there a way to store more complex data there?

example: a List of a basic class Person with a name and age. I attempted to do it as:

Saving the data:

roamingSettings.Values["peopleList"] = people;

Loading the Data:

people = (List)roamingSettings.Values["peopleList"];

WinRT information: Error trying to serialize the value to be written to the application data store. when saving the data I get the error "Data of this type is not supported"

So, maybe all you can save is string values -- but I have not seen that specified anywhere either.

回答1:

Yes, you can save your values to raoming data as a collection. The solution for your problem is ApplicationDataCompositeValue class

See http://msdn.microsoft.com/en-us/library/windows/apps/windows.storage.applicationdatacompositevalue.aspx for more information

As you mentioned, You are developing in C# , following is the code for your problem I imagined, you have a Person class with two members

class person
{
int PersonID;
string PersonName
}

Now, to read and write values for this class, here is the code

First in the constructor of your Window class, under the InitializeComponent();, create an object of roaming settings

Windows.Storage.ApplicationDataContainer roamingSettings = Windows.Storage.ApplicationData.Current.RoamingSettings;

To Write to a composition, use the following code

void write (Person Peopleobj)
{
Windows.Storage.ApplicationDataCompositeValue composite = new Windows.Storage.ApplicationDataCompositeValue();
composite["PersonID"] = Peopleobj.PersonID;
composite["PersonName"] = Peopleobj.PersonName;
roamingSettings.Values["classperson"] = composite;
}

To Read a Person object, use the following code

void DisplayOutput()
    {
        ApplicationDataCompositeValue composite = (ApplicationDataCompositeValue)roamingSettings.Values["classperson"];

        if (composite == null)
        {
            // "Composite Setting: <empty>";
        }
        else
        {
        Peopleobj.PersonID = composite["PersonID"] ;
        Peopleobj.PersonName = composite["PersonName"];

        }

         }

来源：https://stackoverflow.com/questions/13473136/windows-8-app-roaming-storage-with-custom-class

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windows-8

microsoft-metro