== 菜鸟级选手试验在EF6中使用Sqlite，零EF基础，少量Sqlite基础。经过断断续续的很长时间 - _ -！
>>连接
1. 安装
使用目前最新版本EF6.1，Sqlite1.0.93.0。直接NuGet安装：
2. 配置
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
|
<?xml version="1.0" encoding="utf-8"?>
<configuration> <configSections>
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
</configSections>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
</startup>
<connectionStrings>
<add name="SqlliteEF6" connectionString="Data Source=Data\EF6.db" providerName="System.Data.SQLite" /> </connectionStrings>
<entityFramework>
<providers>
<provider invariantName="System.Data.SQLite" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
<provider invariantName="System.Data.SQLite.EF6" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
</providers>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
<parameters>
<parameter value="v11.0" />
</parameters>
</defaultConnectionFactory>
</entityFramework>
<system.data>
<DbProviderFactories>
<remove invariant="System.Data.SQLite" />
<add name="SQLite Data Provider" invariant="System.Data.SQLite" description="Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
<remove invariant="System.Data.SQLite.EF6" />
<add name="SQLite Data Provider (Entity Framework 6)" invariant="System.Data.SQLite.EF6" description=".Net Framework Data Provider for SQLite (Entity Framework 6)" type="System.Data.SQLite.EF6.SQLiteProviderFactory, System.Data.SQLite.EF6" />
</DbProviderFactories>
</system.data>
</configuration> |
3. 设置数据库
EF中数据库操作继承DBContext。需要指定数据连接，名称和config配置一致，否则默认使用Sqlserver。
SQLite可以重载创建。
|
1
2
3
4
5
6
7
8
9
10
11
|
public class EF6Context : DbContext
{
public EF6Context(string databaseName = "SqlliteEF6")
: base(databaseName)
{
}
public DbSet<User> Users { set; get; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{}
} |
>>注意事项
1. Sqlite中不能自动创建数据库和新建表，需要额外的操作
>> 数据类型插入获取
1. 自增ID
Sqlite中需要设置AUTOINCREMENT，如下：
|
1
|
Id INTEGER PRIMARY KEY AUTOINCREMENT,
|
需要引用System.ComponentModel.DataAnnotations，System.ComponentModel.DataAnnotations.Schema，类中写明
|
1
2
|
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]public Int64 Id { get; set; }
|
2. 限定Table
默认数据库获取为DBContext中定义的名称，限定对应的Table，需要在类上指明，如下：
|
1
2
3
|
[Table("User")]
public class User
{... |
3. 枚举型
目前直接能使用，注意需要在定义表时限定不能为NULL,否则为NULL时获取会报错。定义时如下定义：
|
1
|
public enum TestENUM : long { A, B, C };
|
4. 其它
目前SQlite中支持浮点数、时间、二进制数据、字符串等。创建表示例：
|
1
2
3
4
5
6
7
8
9
|
NorthwindContext context = new NorthwindContext();
string sql = @" CREATE TABLE User (
Id INTEGER PRIMARY KEY AUTOINCREMENT,
Name varchar (20),
Time timestamp,
Data blob,
Val REAL,
TestE INTEGER);";
context.Database.ExecuteSqlCommand(sql, new object[1]);
|
定义类示例：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
|
[Table("User")]
public class User
{ public enum TestENUM : long { A, B, C };
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Int64 Id { get; set; }
[StringLength(30)]
public string Name { get; set; }
public byte[] Data { get; set; }
public double Val { get; set; }
public DateTime Time { get; set; }
public TestENUM TestE { get; set; }
} |
|
1
2
3
4
5
6
7
8
9
10
11
|
public class EF6Context : DbContext
{
public EF6Context(string databaseName = "SqlliteEF6")
: base(databaseName)
{
}
public DbSet<User> Users { set; get; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{}
} |
调用示例：
|
1
2
3
|
NorthwindContext context = new NorthwindContext();
context.Users.Add(new User() { Data = new byte[] { 1, 2, 3, 4 }, Name = "aa22", Time = DateTime.Now, Val = 2.2, TestE = User.TestENUM.B });
context.SaveChanges(); |
|
1
2
3
|
NorthwindContext context = new NorthwindContext();
context.Users.OrderBy(c => c.Name).Load();this.dataGrid.ItemsSource = context.Users.Local;
|
以上代码测试正常。源码下载