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C# Windows phone 8中使用SQLite的本地数据库_C#_Wpf_Sqlite_Windows Phone 8 - Fatal编程技术网

C# Windows phone 8中使用SQLite的本地数据库

C# Windows phone 8中使用SQLite的本地数据库,c#,wpf,sqlite,windows-phone-8,C#,Wpf,Sqlite,Windows Phone 8,我在WindowsPhone8中创建了一个带有本地数据库的测试应用程序,但出现错误,我的项目无法创建sqlite数据库 你能帮我吗 运行时错误如下: mscorlib.ni.dll中发生“System.Reflection.TargetInvocationException”类型的异常,但未在用户代码中处理 附加信息:调用目标已引发异常 此行:val=m.GetValue(obj,null) Personclass: namespace PhoneApp4 { public class

我在WindowsPhone8中创建了一个带有本地数据库的测试应用程序,但出现错误,我的项目无法创建sqlite数据库

你能帮我吗

运行时错误如下:

mscorlib.ni.dll中发生“System.Reflection.TargetInvocationException”类型的异常,但未在用户代码中处理

附加信息:调用目标已引发异常

此行:val=m.GetValue(obj,null)

Person
class:

namespace PhoneApp4
{
    public class person
    {
        [SQLite.AutoIncrement , SQLite.PrimaryKey]
        public int ID { get; set; }
        public string FullName { get; set; }
    }
}
mainpage.xaml.cs

namespace PhoneApp4
{
    public partial class MainPage : PhoneApplicationPage
    {
        // Constructor
        public MainPage()
        {
            InitializeComponent();

            // Sample code to localize the ApplicationBar
            //BuildLocalizedApplicationBar();
        }

        private async void BTO_save_Tap(object sender, System.Windows.Input.GestureEventArgs e)
        {
            SQLiteAsyncConnection conn = new SQLiteAsyncConnection(Path.Combine(ApplicationData.Current.LocalFolder.Path, "dbsqlite.sqlite"), true);
            person person = new person
            {
                FullName = TB_save.Text
            };

            await conn.InsertAsync(person);
        }

        private async void BTO_search_Tap(object sender, System.Windows.Input.GestureEventArgs e)
        {
            SQLiteAsyncConnection conn = new SQLiteAsyncConnection(Path.Combine(ApplicationData.Current.LocalFolder.Path, "people.db"), true);

            var query = conn.Table<person>().Where(x => x.ID == Convert.ToInt32(TB_search.Text));
            var result = await query.ToListAsync();
            foreach (var item in result)
            {
                LB_search.Items.Add(item.ID.ToString() + "    " + item.FullName.ToString());
            }
        }
private void Application_Launching(object sender, LaunchingEventArgs e)
{
    string dbPath = Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, "dbsqlite.sqlite");
        using (var db = new SQLiteConnection(dbPath))
        {
            db.CreateTable<person>();
        }
}

// Code to execute when the application is activated (brought to foreground)
// This code will not execute when the application is first launched
private void Application_Activated(object sender, ActivatedEventArgs e)
{
    string dbPath = Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, "dbsqlite.sqlite");
    if (FileExists("dbsqlite.sqlite").Result)
    {
        using (var db = new SQLiteConnection(dbPath))
        {
            db.CreateTable<person>();
        }
    }
}

// Code to execute when the application is deactivated (sent to background)
// This code will not execute when the application is closing
private void Application_Deactivated(object sender, DeactivatedEventArgs e)
{
    string dbPath = Path.Combine(Windows.Storage.ApplicationData.Current.LocalFolder.Path, "dbsqlite.sqlite");
    if (!FileExists("dbsqlite.sqlite").Result)
    {
        using (var db = new SQLiteConnection(dbPath))
        {
            db.CreateTable<person>();
        }
    }
}
看到这个样本了吗

public static async void CreateDbAsync()
{ 
App.Connection=新的SQLiteAsyncConnection(“UniversityDB.db”);
var universityTask=App.Connection.CreateTableAsync();
var studentTask=App.Connection.CreateTableAsync();
等待任务.WhenAll(新任务[]{universityTask,studentTask});
}

您使用的是哪个SQLite库?您可以尝试一下并报告吗?
 private async void Application_Launching(object sender, LaunchingEventArgs e) 
        { 
            try 
            { 
                await ApplicationData.Current.LocalFolder.GetFileAsync("UniversityDB.db"); 
                Connection = new SQLiteAsyncConnection("UniversityDB.db"); 
            } 
            catch (FileNotFoundException) 
            { 
                DataService.CreateDbAsync(); 
            } 
        }
public static async void CreateDbAsync() 
        { 
            App.Connection = new SQLiteAsyncConnection("UniversityDB.db"); 

            var universityTask = App.Connection.CreateTableAsync<University>(); 
            var studentTask = App.Connection.CreateTableAsync<Student>(); 

            await Task.WhenAll(new Task[] { universityTask, studentTask }); 
        }