windowsphone8教程08,WindowsPhone本地存储

本文由麦可网整理，转载请注明出处08，WindowsPhone本地存储内容预告：WindowsPhone的数据库支持LINQtoSQL性能和最佳实践LINQtoEverything:支持复杂的结构：本文由麦可网整理，转载请注明出处支持外键：WebService缓存：本地存储：架构：本文由麦可网整理，转载请注明出处对象：定义表：//Definethetablesinthedatabase[Table]本文由麦可网整理，转载请注明出处publicclassWine:INotifyPropertyChanged,INotifyPropertyChanging{privatestringwineID;privatestringname;[Column(IsPrimaryKey=true)]publicstringWineID{get{returnwineID;}set{InvokePropertyChanging(newPropertyChangingEventArgs(WineID));wineID=value;InvokePropertyChanged(newPropertyChangedEventArgs(WineID));}}[Column]publicstringName{...}...}定义数据上下文：//Definethedatacontext.publicpartialclassWineDataContext:DataContext{publicTableWineWines;publicTableVineyardVineyards;publicWineDataContext(stringconnection):base(connection){}}...//Createthedatabasefromdatacontext,usingaconnectionstringDataContextdb=newWineDataContext(isostore:/wineDB.sdf);if(!db.DatabaseExists())db.CreateDatabase();用SQLMetal代码生成工具:c:\Sqlmetal/code:northwindEntities.cs/context:NorthwindDataContext/pluralizenorthwind.sdf查询：//Createthedatabaseformdatacontext,usingaconnectionstringDataContextdb=newWineDataContext(isostore:/wineDB.sdf);//Findallwinescurrentlyathome,orderedbydateacquiredvarq=fromwindb.Wineswherew.Varietal.Name==“Shiraz”&&w.IsAtHome==trueorderbyw.DateAcquiredselectw;插入，更新，删除：别忘了submitChanges本文由麦可网整理，转载请注明出处插入：WinenewWine=newWine{WineID=“1768,Name=“WindowsPhoneSyrah,Description=“Boldandspicy};db.Wines.InsertOnSubmit(newWine);db.SubmitChanges();更新：Winewine=(fromwindb.Wineswherew.WineID==“1768selectw).First();wine.Description=“Hintsofplumandmelon;db.SubmitChanges();删除：varvineyardsToDelete=fromVineyardsvindb.Vineyardswherev.Country==“Australia”selectv;db.Vineyards.DeleteAllOnSubmit(vineyardsToDelete);db.SubmitChanges();更新数据库结构：WineDataContextwineDC=newWineDataContext(App.WineDBConnectionString);DatabaseSchemaUpdaterdsu=wineDC.CreateDatabaseSchemaUpdater();if(dsu.DatabaseSchemaVersion==1){dsu.AddColumnWine(BottleType);dsu.DatabaseSchemaVersion=2;dsu.Execute();}性能和最佳实践：保持修改的集合很小，换句话说，尽早提交修改，以避免程序终止时数据丢失。本文由麦可网整理，转载请注明出处用后台线程。优化只读查询。提前填充大量数据。用对的工具，大量复杂的数据用数据库，小数据用独立存储。