Silverlight:电话数据库项目 [英] Silverlight: Phone Database Project

问题描述

大家好，

我正在使用以下代码创建数据库:

(名称是常量字符串)

Hi everyone,

I am creating a database using the following code:

(name is constant string)

using SilverlightPhoneDatabase;
Database DB;
const string name = "MyDatabase";

private void CreateDBTest()
        {
            if (Database.DoesDatabaseExists(name) == false)
            {
                if (Database.CreateDatabase(name) != null)
                {
                    DB = Database.CreateDatabase(name);
                    DB.Save();
                }
            }
            else
            {
                tbDbExists.Text = "DB Already Exists...";
            }
        }

然后创建一个表格-

and then I create a table -

private void CreateTableTest()
        {
            DB = Database.OpenDatabase(name);

            DB.CreateTable<person>();

            if (DB.Table<person>() != null)
            {
                DB.Table<person>().Add(NewPerson());
                if (DB.Table<person>().Count == 1)
                {
                    tbTableCreated.Text = "Table Created...";
                }
            }
            else
            {
                tbTableCreated.Text = "Table Not Created...";
            }
        }</person></person></person></person>

其中Person是具有FirstName，LastName等属性的类.
NewPerson是一个功能-

where Person is a class with properties like FirstName, LastName etc.
and NewPerson is a function -

private Person NewPerson()
        {
            return new Person() 
            { 
                FirstName = "John", LastName = "Doe",
                Salary = 100          
             };
        }

现在，当我创建数据库时，它会保留，并且每次我尝试使用相同的名称创建数据库时，都会说该数据库已经存在.可以，但是当我一次创建表时，它不会在下一次持久化.我该怎么办?

谢谢.

Now when I create the database, it persists, and each time I try to create the database with same name, it says that it already exists. This is OK but when I create the table once, it doesn''t persist for the next time. What should I do?

Thanks.

推荐答案

相同的问题.您缺少DB.Save().

Same problem. You are missing DB.Save().

好 我明白了
我已经在CreateTableTest()中添加了DB.Save()
现在我的表是持久的.

但是现在我又遇到了另一个问题
它不是要删除行-

Ok i got it
I''ve added DB.Save()in CreateTableTest()
and now my table is persistent.

But now i''ve another problem
that it is not deleting rows -

private void DeleteRecord()
        {
            DB = Database.OpenDatabase(name);

            var query = (from onePerson in DB.Table<person>()
                         where onePerson.Salary == 100
                         select onePerson);

            DB.Table<person>().Remove(query.ElementAt(0));
        }</person></person>

我也尝试过-

also i''ve tried -

DB.Table<person>().RemoveRange((person) => { return (person.Salary >= 1); });</person>

没有给出任何错误，
但是当我检查时，没有行被删除....

not giving any error,
but when i check, no row is deleted....

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