使用SQL server compact toolbox的Windows phone应用程序上的C#本地数据库

我是WP开发的新手。我只想创建一个简单的数据库并使用它

我创建了一个数据库，表是Member，3列是ID、FirstName、LastName。然后我使用SQLServerCompactToolbox生成datacontext

最后，我尝试制作一个完整的应用程序。但是当我输入FirstName和LastName时，它不会显示结果。请帮帮我

代码如下：

Namecontext.cs

namespace PhoneApp6
{
    using System.Data.Linq;
    using System.Data.Linq.Mapping;
    using System.Data;
    using System.Collections.Generic;
    using System.Reflection;
    using System.Linq;
    using System.Linq.Expressions;
    using System.ComponentModel;
    using System;

using System.IO;
using System.IO.IsolatedStorage;
using Microsoft.Phone.Data.Linq.Mapping;
using Microsoft.Phone.Data.Linq;


public class DebugWriter : TextWriter
{
    private const int DefaultBufferSize = 256;
    private System.Text.StringBuilder _buffer;

    public DebugWriter()
    {
        BufferSize = 256;
        _buffer = new System.Text.StringBuilder(BufferSize);
    }

    public int BufferSize
    {
        get;
        private set;
    }

    public override System.Text.Encoding Encoding
    {
        get { return System.Text.Encoding.UTF8; }
    }

    #region StreamWriter Overrides
    public override void Write(char value)
    {
        _buffer.Append(value);
        if (_buffer.Length >= BufferSize)
            Flush();
    }

    public override void WriteLine(string value)
    {
        Flush();

        using(var reader = new StringReader(value))
        {
            string line; 
            while( null != (line = reader.ReadLine()))
                System.Diagnostics.Debug.WriteLine(line);
        }
    }

    protected override void Dispose(bool disposing)
    {
        if (disposing)
            Flush();
    }

    public override void Flush()
    {
        if (_buffer.Length > 0)
        {
            System.Diagnostics.Debug.WriteLine(_buffer);
            _buffer.Clear();
        }
    }
    #endregion
}


    public partial class NameContext : System.Data.Linq.DataContext
    {

        public bool CreateIfNotExists()
        {
            bool created = false;
            if (!this.DatabaseExists())
            {
                string[] names = this.GetType().Assembly.GetManifestResourceNames();
                string name = names.Where(n => n.EndsWith(FileName)).FirstOrDefault();
                if (name != null)
                {
                    using (Stream resourceStream = Assembly.GetExecutingAssembly().GetManifestResourceStream(name))
                    {
                        if (resourceStream != null)
                        {
                            using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
                            {
                                using (IsolatedStorageFileStream fileStream = new IsolatedStorageFileStream(FileName, FileMode.Create, myIsolatedStorage))
                                {
                                    using (BinaryWriter writer = new BinaryWriter(fileStream))
                                    {
                                        long length = resourceStream.Length;
                                        byte[] buffer = new byte[32];
                                        int readCount = 0;
                                        using (BinaryReader reader = new BinaryReader(resourceStream))
                                        {
                                            // read file in chunks in order to reduce memory consumption and increase performance
                                            while (readCount < length)
                                            {
                                                int actual = reader.Read(buffer, 0, buffer.Length);
                                                readCount += actual;
                                                writer.Write(buffer, 0, actual);
                                            }
                                        }
                                    }
                                }
                            }
                            created = true;
                        }
                        else
                        {
                            this.CreateDatabase();
                            created = true;
                        }
                    }
                }
                else
                {
                    this.CreateDatabase();
                    created = true;
                }
            }
            return created;
        }


        public bool LogDebug
        {
            set
            {
                if (value)
                {
                    this.Log = new DebugWriter();
                }
            }
        }

        public static string ConnectionString = "Data Source=isostore:/Name.sdf";

        public static string ConnectionStringReadOnly = "Data Source=appdata:/Name.sdf;File Mode=Read Only;";

        public static string FileName = "Name.sdf";

        public NameContext(string connectionString) : base(connectionString)
        {
            OnCreated();
        }

    #region Extensibility Method Definitions
    partial void OnCreated();
    partial void InsertMember(Member instance);
    partial void UpdateMember(Member instance);
    partial void DeleteMember(Member instance);
    #endregion

        public System.Data.Linq.Table<Member> Member
        {
            get
            {
                return this.GetTable<Member>();
            }
        }
    }

    [global::System.Data.Linq.Mapping.TableAttribute()]
    public partial class Member : INotifyPropertyChanging, INotifyPropertyChanged
    {

        private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);

        private int _ID;

        private string _FirstName;

        private string _LastName;

    #region Extensibility Method Definitions
    partial void OnLoaded();
    partial void OnValidate(System.Data.Linq.ChangeAction action);
    partial void OnCreated();
    partial void OnIDChanging(int value);
    partial void OnIDChanged();
    partial void OnFirstNameChanging(string value);
    partial void OnFirstNameChanged();
    partial void OnLastNameChanging(string value);
    partial void OnLastNameChanged();
    #endregion

        public Member()
        {
            OnCreated();
        }

        [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_ID", DbType="Int NOT NULL", IsPrimaryKey=true)]
        public int ID
        {
            get
            {
                return this._ID;
            }
            set
            {
                if ((this._ID != value))
                {
                    this.OnIDChanging(value);
                    this.SendPropertyChanging();
                    this._ID = value;
                    this.SendPropertyChanged("ID");
                    this.OnIDChanged();
                }
            }
        }

        [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_FirstName", DbType="NVarChar(100) NOT NULL", CanBeNull=false)]
        public string FirstName
        {
            get
            {
                return this._FirstName;
            }
            set
            {
                if ((this._FirstName != value))
                {
                    this.OnFirstNameChanging(value);
                    this.SendPropertyChanging();
                    this._FirstName = value;
                    this.SendPropertyChanged("FirstName");
                    this.OnFirstNameChanged();
                }
            }
        }

        [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_LastName", DbType="NVarChar(100) NOT NULL", CanBeNull=false)]
        public string LastName
        {
            get
            {
                return this._LastName;
            }
            set
            {
                if ((this._LastName != value))
                {
                    this.OnLastNameChanging(value);
                    this.SendPropertyChanging();
                    this._LastName = value;
                    this.SendPropertyChanged("LastName");
                    this.OnLastNameChanged();
                }
            }
        }

        public event PropertyChangingEventHandler PropertyChanging;

        public event PropertyChangedEventHandler PropertyChanged;

        protected virtual void SendPropertyChanging()
        {
            if ((this.PropertyChanging != null))
            {
                this.PropertyChanging(this, emptyChangingEventArgs);
            }
        }

        protected virtual void SendPropertyChanged(String propertyName)
        {
            if ((this.PropertyChanged != null))
            {
                this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }
}

视图模型：

namespace PhoneApp6
{
    public partial class Showlist : PhoneApplicationPage
    {
        public Showlist()
        {
            InitializeComponent();
        }

        private void appBarOkButton_Click(object sender, EventArgs e)
        {
            if ((Addfirstname.Text.Length > 0) & (Addlastname.Text.Length >0))
            {
                Member add = new Member
                {
                    FirstName = Addfirstname.Text,
                    LastName = Addlastname.Text,
                };

                // Add the name to the ViewModel.
                App.ViewModel.AddName(add);

                // Return to the main page.
                if (NavigationService.CanGoBack)
                {
                    NavigationService.GoBack();
                }
            }
        }

        private void appBarCancelButton_Click(object sender, EventArgs e)
        {
            // Return to the main page.
            if (NavigationService.CanGoBack)
            {
                NavigationService.GoBack();
            }
        }
    }
}

namespace PhoneApp6
{
    public class NameViewModel : INotifyPropertyChanged
    {
        #region INotifyPropertyChanged Members   
        public event PropertyChangedEventHandler PropertyChanged;

        // Used to notify Silverlight that a property has changed.
        private void NotifyPropertyChanged(string propertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
        #endregion
        // LINQ to SQL data context for the local database.
        private NameContext nameDB;

        // Class constructor, create the data context object.
        public NameViewModel(string nameDBConnectionString)
        {
            nameDB = new NameContext(nameDBConnectionString);
        }

        //FirstName
        private ObservableCollection<Member> _firstname;
        public ObservableCollection<Member> FirstName
        {
            get { return _firstname; }
            set 
            {
                _firstname=value;
                NotifyPropertyChanged("FirstName");
            }
        }

        //LastName
        private ObservableCollection<Member> _lastname;
        public ObservableCollection<Member> LastName
        {
            get { return _lastname; }
            set
            {
                _lastname = value;
                NotifyPropertyChanged("LastName");
            }
        }

        // Write changes in the data context to the database.
        public void SaveChangesToDB()
        {
            nameDB.SubmitChanges();
        }

         // Query database and load the collections and list 
        public void LoadCollectionsFromDatabase()
        {
            // Specify the query for First in the database.
            var firstnameInDB = from Member first in nameDB.Member
                                select first;
            var lastnameInDB = from Member last in nameDB.Member
                                select last;
            FirstName = new ObservableCollection<Member>(firstnameInDB);
            LastName = new ObservableCollection<Member>(lastnameInDB);  
        }

        //add
        public void AddName(Member add)
        {

            // Remove the to-do item from the "all" observable collection.
            FirstName.Add(add);
            LastName.Add(add);





            nameDB.SubmitChanges();
        }


        //delete
        public void DeleteName(Member delete)
        {

            // Remove the to-do item from the "all" observable collection.
            FirstName.Remove(delete);
            LastName.Remove(delete);


            nameDB.Member.DeleteOnSubmit(delete);


            nameDB.SubmitChanges();
        }
    }
}

<StackPanel Orientation="Vertical" Margin="0,0,0,366">
                <TextBlock Text="FirstName" HorizontalAlignment="Center" FontSize="20" />
                <TextBlock Text="{Binding FN}"  FontSize="20" Foreground="Yellow"  />
            </StackPanel>

            <StackPanel Orientation="Vertical" Margin="0,315,0,0">
                <TextBlock Text="LastName" HorizontalAlignment="Center" FontSize="20" />
                <TextBlock Text="{Binding LN}" FontSize="20" Foreground="Yellow"  />
            </StackPanel>

namespace PhoneApp6
{
    public partial class Page1: PhoneApplicationPage
    {
        public Page1()
        {
            InitializeComponent();
            // Set the page DataContext property to the ViewModel.
            this.DataContext = App.ViewModel;
        }
        protected override void OnNavigatedFrom(System.Windows.Navigation.NavigationEventArgs e)
        {
            // Save changes to the database.
            App.ViewModel.SaveChangesToDB();
        }

    }
}

---

你真的应该把你的代码片段删减到与你的问题相关的部分。很抱歉，我不知道它到底错在哪里。我是新手。。。请帮助我检查这一点，从学习如何调试应用程序开始。一个真正好的开始是从你认为“它没有显示结果”的意思开始。然后从那里开始倒转。你当初是怎么写这些的？我只是想知道，几天前我看到了类似的东西，它看起来真的太复杂了。