LINQ to SQL 中的程式碼產生
您可以使用物件關聯式設計工具或 SQLMetal 命令列工具,來產生表示資料庫的程式碼。 無論使用哪種工具,端對端程式碼產生都可分為三個階段:
- DBML Extractor 會從資料庫擷取結構描述資訊,再將這些資訊重新組成 XML 格式的 DBML 檔案。
- 「DBML 驗證程式」會掃描此 DBML 檔案,檢查是否有錯誤。
- 如果沒有發現驗證錯誤,檔案會傳遞給程式碼產生器。
如需詳細資訊,請參閱 SqlMetal.exe (程式碼產生工具)。 使用 Visual Studio 的開發人員也可以使用物件關聯式設計工具來產生程式碼。 請參閱 Visual Studio 中的 LINQ to SQL 工具。
DBML 擷取器
DBML 擷取器是 LINQ to SQL 元件,其會將資料庫中繼資料當作輸入,然後輸出成 DBML 檔案。
程式碼產生器
程式碼產生器是 LINQ to SQL 元件,可將 DBML 檔案轉譯成 Visual Basic、C# 或 XML 對應檔案。
XML 結構描述定義檔
DBML 檔案必須根據下列結構描述定義 (XSD 檔案) 進行驗證。
這個結構描述定義檔與用來驗證外部對應檔案的結構描述定義檔不同。 如需詳細資訊,請參閱外部對應。
注意
Visual Studio 使用者也可在 [XML 結構描述] 對話方塊找到此 XSD 檔案,檔名為 "DbmlSchema.xsd"。 若要正確使用 XSD 檔案來驗證 DBML 檔案,請參閱操作說明:驗證 DBML 與外部對應檔案。
<?xml version="1.0" encoding="utf-16"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://schemas.microsoft.com/linqtosql/dbml/2007" xmlns="http://schemas.microsoft.com/linqtosql/dbml/2007"
elementFormDefault="qualified" >
<xs:element name="Database" type="Database" />
<xs:complexType name="Database">
<xs:sequence>
<xs:element name="Connection" type="Connection" minOccurs="0" maxOccurs="1" />
<xs:element name="Table" type="Table" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="Function" type="Function" minOccurs="0" maxOccurs="unbounded" />
</xs:sequence>
<xs:attribute name="Name" type="xs:string" use="optional" />
<xs:attribute name="EntityNamespace" type="xs:string" use="optional" />
<xs:attribute name="ContextNamespace" type="xs:string" use="optional" />
<xs:attribute name="Class" type="xs:string" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="ClassModifier" use="optional" />
<xs:attribute name="BaseType" type="xs:string" use="optional" />
<xs:attribute name="Provider" type="xs:string" use="optional" />
<xs:attribute name="ExternalMapping" type="xs:boolean" use="optional" />
<xs:attribute name="Serialization" type="SerializationMode" use="optional" />
<xs:attribute name="EntityBase" type="xs:string" use="optional" />
</xs:complexType>
<xs:complexType name="Table">
<xs:all>
<xs:element name="Type" type="Type" minOccurs="1" maxOccurs="1" />
<xs:element name="InsertFunction" type="TableFunction" minOccurs="0" maxOccurs="1" />
<xs:element name="UpdateFunction" type="TableFunction" minOccurs="0" maxOccurs="1" />
<xs:element name="DeleteFunction" type="TableFunction" minOccurs="0" maxOccurs="1" />
</xs:all>
<xs:attribute name="Name" type="xs:string" use="required" />
<xs:attribute name="Member" type="xs:string" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="MemberModifier" use="optional" />
</xs:complexType>
<xs:complexType name="Type">
<xs:sequence>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element name="Column" type="Column" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="Association" type="Association" minOccurs="0" maxOccurs="unbounded" />
</xs:choice>
<xs:element name="Type" type="Type" minOccurs="0" maxOccurs="unbounded" />
</xs:sequence>
<xs:attribute name="IdRef" type="xs:IDREF" use="optional" />
<xs:attribute name="Id" type="xs:ID" use="optional" />
<xs:attribute name="Name" type="xs:string" use="optional" />
<xs:attribute name="InheritanceCode" type="xs:string" use="optional" />
<xs:attribute name="IsInheritanceDefault" type="xs:boolean" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="ClassModifier" use="optional" />
</xs:complexType>
<xs:complexType name="Column">
<xs:attribute name="Name" type="xs:string" use="optional" />
<xs:attribute name="Member" type="xs:string" use="optional" />
<xs:attribute name="Storage" type="xs:string" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="MemberModifier" use="optional" />
<xs:attribute name="Type" type="xs:string" use="required" />
<xs:attribute name="DbType" type="xs:string" use="optional" />
<xs:attribute name="IsReadOnly" type="xs:boolean" use="optional" />
<xs:attribute name="IsPrimaryKey" type="xs:boolean" use="optional" />
<xs:attribute name="IsDbGenerated" type="xs:boolean" use="optional" />
<xs:attribute name="CanBeNull" type="xs:boolean" use="optional" />
<xs:attribute name="UpdateCheck" type="UpdateCheck" use="optional" />
<xs:attribute name="IsDiscriminator" type="xs:boolean" use="optional" />
<xs:attribute name="Expression" type="xs:string" use="optional" />
<xs:attribute name="IsVersion" type="xs:boolean" use="optional" />
<xs:attribute name="IsDelayLoaded" type="xs:boolean" use="optional" />
<xs:attribute name="AutoSync" type="AutoSync" use="optional" />
</xs:complexType>
<xs:complexType name="Association">
<xs:attribute name="Name" type="xs:string" use="required" />
<xs:attribute name="Member" type="xs:string" use="required" />
<xs:attribute name="Storage" type="xs:string" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="MemberModifier" use="optional" />
<xs:attribute name="Type" type="xs:string" use="required" />
<xs:attribute name="ThisKey" type="xs:string" use="optional" />
<xs:attribute name="OtherKey" type="xs:string" use="optional" />
<xs:attribute name="IsForeignKey" type="xs:boolean" use="optional" />
<xs:attribute name="Cardinality" type="Cardinality" use="optional" />
<xs:attribute name="DeleteRule" type="xs:string" use="optional" />
<xs:attribute name="DeleteOnNull" type="xs:boolean" use="optional" />
</xs:complexType>
<xs:complexType name="Function">
<xs:sequence>
<xs:element name="Parameter" type="Parameter" minOccurs="0" maxOccurs="unbounded" />
<xs:choice>
<xs:element name="ElementType" type="Type" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="Return" type="Return" minOccurs="0" maxOccurs="1" />
</xs:choice>
</xs:sequence>
<xs:attribute name="Name" type="xs:string" use="required" />
<xs:attribute name="Id" type="xs:ID" use="optional" />
<xs:attribute name="Method" type="xs:string" use="optional" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
<xs:attribute name="Modifier" type="MemberModifier" use="optional" />
<xs:attribute name="HasMultipleResults" type="xs:boolean" use="optional" />
<xs:attribute name="IsComposable" type="xs:boolean" use="optional" />
</xs:complexType>
<xs:complexType name="TableFunction">
<xs:sequence>
<xs:element name="Argument" type="TableFunctionParameter" minOccurs="0" maxOccurs="unbounded" />
<xs:element name="Return" type="TableFunctionReturn" minOccurs="0" maxOccurs="1" />
</xs:sequence>
<xs:attribute name="FunctionId" type="xs:IDREF" use="required" />
<xs:attribute name="AccessModifier" type="AccessModifier" use="optional" />
</xs:complexType>
<xs:complexType name="Parameter">
<xs:attribute name="Name" type="xs:string" use="required" />
<xs:attribute name="Parameter" type="xs:string" use="optional" />
<xs:attribute name="Type" type="xs:string" use="required" />
<xs:attribute name="DbType" type="xs:string" use="optional" />
<xs:attribute name="Direction" type="ParameterDirection" use="optional" />
</xs:complexType>
<xs:complexType name="Return">
<xs:attribute name="Type" type="xs:string" use="required" />
<xs:attribute name="DbType" type="xs:string" use="optional" />
</xs:complexType>
<xs:complexType name="TableFunctionParameter">
<xs:attribute name="Parameter" type="xs:string" use="required" />
<xs:attribute name="Member" type="xs:string" use="required" />
<xs:attribute name="Version" type="Version" use="optional" />
</xs:complexType>
<xs:complexType name="TableFunctionReturn">
<xs:attribute name="Member" type="xs:string" use="required" />
</xs:complexType>
<xs:complexType name="Connection">
<xs:attribute name="Provider" type="xs:string" use="required" />
<xs:attribute name="Mode" type="ConnectionMode" use="optional" />
<xs:attribute name="ConnectionString" type="xs:string" use="optional" />
<xs:attribute name="SettingsObjectName" type="xs:string" use="optional" />
<xs:attribute name="SettingsPropertyName" type="xs:string" use="optional" />
</xs:complexType>
<xs:simpleType name="ConnectionMode">
<xs:restriction base="xs:string">
<xs:enumeration value="ConnectionString" />
<xs:enumeration value="AppSettings" />
<xs:enumeration value="WebSettings" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="AccessModifier">
<xs:restriction base="xs:string">
<xs:enumeration value="Public" />
<xs:enumeration value="Internal" />
<xs:enumeration value="Protected" />
<xs:enumeration value="ProtectedInternal" />
<xs:enumeration value="Private" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="UpdateCheck">
<xs:restriction base="xs:string">
<xs:enumeration value="Always" />
<xs:enumeration value="Never" />
<xs:enumeration value="WhenChanged" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="SerializationMode">
<xs:restriction base="xs:string">
<xs:enumeration value="None" />
<xs:enumeration value="Unidirectional" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="ParameterDirection">
<xs:restriction base="xs:string">
<xs:enumeration value="In" />
<xs:enumeration value="Out" />
<xs:enumeration value="InOut" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="Version">
<xs:restriction base="xs:string">
<xs:enumeration value="Current" />
<xs:enumeration value="Original" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="AutoSync">
<xs:restriction base="xs:string">
<xs:enumeration value="Never" />
<xs:enumeration value="OnInsert" />
<xs:enumeration value="OnUpdate" />
<xs:enumeration value="Always" />
<xs:enumeration value="Default" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="ClassModifier">
<xs:restriction base="xs:string">
<xs:enumeration value="Sealed" />
<xs:enumeration value="Abstract" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="MemberModifier">
<xs:restriction base="xs:string">
<xs:enumeration value="Virtual" />
<xs:enumeration value="Override" />
<xs:enumeration value="New" />
<xs:enumeration value="NewVirtual" />
</xs:restriction>
</xs:simpleType>
<xs:simpleType name="Cardinality">
<xs:restriction base="xs:string">
<xs:enumeration value="One" />
<xs:enumeration value="Many" />
</xs:restriction>
</xs:simpleType>
</xs:schema>
範例 DBML 檔案
下列程式碼是從 Northwind 範例資料庫所建立 DBML 檔案的摘錄。 您可以搭配 /xml 選項一起使用 SQLMetal,以產生完整檔案。 如需詳細資訊,請參閱 SqlMetal.exe (程式碼產生工具)。
<?xml version="1.0" encoding="utf-16"?>
<Database Name="northwnd" Class="Northwnd" xmlns="http://schemas.microsoft.com/dsltools/DLinqML">
<Table Name="Customers">
<Type Name="Customer">
<Column Name="CustomerID" Type="System.String" DbType="NChar(5) NOT NULL" IsPrimaryKey="True" CanBeNull="False" />
<Column Name="CompanyName" Type="System.String" DbType="NVarChar(40) NOT NULL" CanBeNull="False" />
<Column Name="ContactName" Type="System.String" DbType="NVarChar(30)" CanBeNull="True" />
<Column Name="ContactTitle" Type="System.String" DbType="NVarChar(30)" CanBeNull="True" />
<Column Name="Address" Type="System.String" DbType="NVarChar(60)" CanBeNull="True" />
<Column Name="City" Type="System.String" DbType="NVarChar(15)" CanBeNull="True" />
<Column Name="Region" Type="System.String" DbType="NVarChar(15)" CanBeNull="True" />
<Column Name="PostalCode" Type="System.String" DbType="NVarChar(10)" CanBeNull="True" />
<Column Name="Country" Type="System.String" DbType="NVarChar(15)" CanBeNull="True" />
<Column Name="Phone" Type="System.String" DbType="NVarChar(24)" CanBeNull="True" />
<Column Name="Fax" Type="System.String" DbType="NVarChar(24)" CanBeNull="True" />
<Association Name="FK_CustomerCustomerDemo_Customers" Member="CustomerCustomerDemos" ThisKey="CustomerID" OtherKey="CustomerID" OtherTable="CustomerCustomerDemo" DeleteRule="NO ACTION" />
<Association Name="FK_Orders_Customers" Member="Orders" ThisKey="CustomerID" OtherKey="CustomerID" OtherTable="Orders" DeleteRule="NO ACTION" />
</Type>
</Table>
</Database>