Method Mapping

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LinqConnect fully supports mapping methods to stored procedures and functions. For example we will map the following methods:

C#csharp

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public class MyDataContext : DataContext {
 
    // ...
 
    public Double? GetPrice(string product) {
        //...
    }
 
    public ISingleResult<Company> GetCompany(string companyName) {
        //...
    }
 
    public IMultipleResults GetMultipleResultSets() {
        //...
    }
}

Visual Basic

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Public Class MyDataContext
    Inherits DataContext

    ' ...

    Public Function GetPrice(product As String) As Nullable(Of Double)
        '...
    End Function

    Public Function GetCompany(companyName As String) As ISingleResult(Of Company)
        '...
    End Function

    Public Function GetMultipleResultSets() As IMultipleResults
        '...
    End Function

End Class

to the stored function GetPrice(PRODUCT IN VARCHAR2) and stored procedures GetCompany(CompanyName IN VARCHAR2) and GetMultipleResultSets(). GetPrice method returns a scalar value, while GetCompany method returns a collection of Company entities, and GetMultipleResultSets returns three collections: two collections of Company and Order entities, and a collection of AddressType coplex types.

Attribute Mapping

Function, Parameter, and ResultType attributes are used for attribute mapping of methods. See the following tables for their properties' descriptions.

Function Attribute Properties

Property	Type	Description
IsComposable	Boolean	Specifies whether a method is mapped to a function (true) or to a stored procedure (false).
Name	String	Specifies the name of the function or stored procedure.

Parameter Attribute Properties

Property	Type	Description
DbType	String	Specifies the type of the parameter.
Name	String	Specifies the name of the parameter.

ResultType Attribute Properties

Property	Type	Description
Type	System.Type	Specifies the valid or expected type mapping for a function having various result types.
Order	System.Int32	Specifies the ordinal number of returned from function resultset.

See the example of the attribute mapping below:

C#csharp

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public class MyDataContext : DataContext {
 
    // ...
 
    [Function(Name="GetPrice", IsComposable=true)]
    public Double? GetPrice([Parameter(Name="PRODUCT", DbType="VARCHAR2")] string product) {
        //...
    }
 
    [Function(Name="GetCompany")]
    public ISingleResult<Company> GetCompany([Parameter(Name="CompanyName", DbType="VARCHAR2")] string companyName) {
        //...
    }
 
    [Function(Name="GetMultipleResultSets")]
    [ResultType(typeof(Company), 1)]
    [ResultType(typeof(Order), 2)]
    [ResultType(typeof(AddressType), 3)]
    public IMultipleResults GetMultipleResultSets() {
        //...
    }
 
}

Visual Basic

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Public Class MyDataContext
    Inherits DataContext

    ' ...

    <[Function](Name:="GetPrice", IsComposable:=True)>
    Public Function GetPrice(<Parameter(Name:="PRODUCT", DbType:="VARCHAR2")> product As String) As Nullable(Of Double)
        '...
    End Function

    <[Function](Name:="GetCompany")>
    Public Function GetCompany(<Parameter(Name:="CompanyName", DbType:="VARCHAR2")> companyName As String) As ISingleResult(Of Company)
        '...
    End Function

    <[Function](Name:="GetMultipleResultSets")> _
    <ResultType(GetType(Company), 1)> _
    <ResultType(GetType(Order), 2)> _
    <ResultType(GetType(AddressType), 3)> _
    Public Function GetMultipleResultSets() As IMultipleResults
        '...
    End Function

End Class

XML Mapping

XML mapping of methods uses Function, Parameter, and ElementType tags.


<Function Name="GetPrice" Method="GetPrice" IsComposable="true" > <Parameter Name="PRODUCT" Member="product" DbType="VARCHAR2" /> </Function> <Function Name="GetCompany" Method="GetCompany"> <Parameter Name="CompanyName" Member="companyName" DbType="VARCHAR2" /> <ElementType Name="Company" /> </Function> <Function Name="GetMultipleResultSets" Method="GetMultipleResultSets"> <ElementType Name="Company" /> <ElementType Name="Order" /> <ElementType Type="AddressType" /> </Function>

<Function Name="GetPrice" Method="GetPrice" IsComposable="true" >
  <Parameter Name="PRODUCT" Member="product" DbType="VARCHAR2" />
</Function>
<Function Name="GetCompany" Method="GetCompany">
  <Parameter Name="CompanyName" Member="companyName" DbType="VARCHAR2" />
  <ElementType Name="Company" />
</Function>
<Function Name="GetMultipleResultSets" Method="GetMultipleResultSets">
  <ElementType Name="Company" />
  <ElementType Name="Order" />
  <ElementType Type="AddressType" />
</Function>

Fluent Mapping

Fluent Mapping of methods is not supported.

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