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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel.Composition.Primitives;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
using System.Linq;
using Microsoft.Internal;
namespace System.ComponentModel.Composition.Hosting
{
public abstract partial class ExportProvider
{
/// <summary>
/// Returns the export with the contract name derived from the specified type parameter,
/// throwing an exception if there is not exactly one matching export.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T}"/> object to return. The contract name is also
/// derived from this type parameter.
/// </typeparam>
/// <returns>
/// The <see cref="Lazy{T}"/> object with the contract name derived from
/// <typeparamref name="T"/>.
/// </returns>
/// <remarks>
/// <para>
/// The returned <see cref="Lazy{T}"/> object is an instance of
/// <see cref="Lazy{T, TMetadataView}"/> underneath, where
/// <c>TMetadataView</c>
/// is <see cref="IDictionary{TKey, TValue}"/> and where <c>TKey</c>
/// is <see cref="string"/> and <c>TValue</c> is <see cref="object"/>.
/// </para>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero <see cref="Lazy{T}"/> objects with the contract name derived
/// from <typeparamref name="T"/> in the <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one <see cref="Lazy{T}"/> objects with the contract name
/// derived from <typeparamref name="T"/> in the <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public Lazy<T>? GetExport<T>()
{
return GetExport<T>((string?)null);
}
/// <summary>
/// Returns the export with the specified contract name, throwing an exception if there
/// is not exactly one matching export.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T}"/> object to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the <see cref="Lazy{T}"/>
/// object to return; or <see langword="null"/> or an empty string ("") to use the
/// default contract name.
/// </param>
/// <returns>
/// The <see cref="Lazy{T}"/> object with the specified contract name.
/// </returns>
/// <remarks>
/// <para>
/// The returned <see cref="Lazy{T}"/> object is an instance of
/// <see cref="Lazy{T, TMetadataView}"/> underneath, where
/// <c>TMetadataView</c>
/// is <see cref="IDictionary{TKey, TValue}"/> and where <c>TKey</c>
/// is <see cref="string"/> and <c>TValue</c> is <see cref="object"/>.
/// </para>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The default contract name is compared using a case-sensitive, non-linguistic
/// comparison using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero <see cref="Lazy{T}"/> objects with the specified contract name
/// in the <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one <see cref="Lazy{T}"/> objects with the specified contract
/// name in the <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public Lazy<T>? GetExport<T>(string? contractName)
{
return GetExportCore<T>(contractName);
}
/// <summary>
/// Returns the export with the contract name derived from the specified type parameter,
/// throwing an exception if there is not exactly one matching export.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T, TMetadataView}"/> object to return. The
/// contract name is also derived from this type parameter.
/// </typeparam>
/// <typeparam name="TMetadataView">
/// The type of the metadata view of the <see cref="Lazy{T, TMetadataView}"/> object
/// to return.
/// </typeparam>
/// <returns>
/// The <see cref="Lazy{T, TMetadataView}"/> object with the contract name derived
/// from <typeparamref name="T"/>.
/// </returns>
/// <remarks>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero <see cref="Lazy{T, TMetadataView}"/> objects with the contract
/// name derived from <typeparamref name="T"/> in the
/// <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one <see cref="Lazy{T, TMetadataView}"/> objects with the
/// contract name derived from <typeparamref name="T"/> in the
/// <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="InvalidOperationException">
/// <typeparamref name="TMetadataView"/> is not a valid metadata view type.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public Lazy<T, TMetadataView>? GetExport<T, TMetadataView>()
{
return GetExport<T, TMetadataView>((string?)null);
}
/// <summary>
/// Returns the export with the specified contract name, throwing an exception if there
/// is not exactly one matching export.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T, TMetadataView}"/> object to return.
/// </typeparam>
/// <typeparam name="TMetadataView">
/// The type of the metadata view of the <see cref="Lazy{T, TMetadataView}"/> object
/// to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the
/// <see cref="Lazy{T, TMetadataView}"/> object to return; or <see langword="null"/>
/// or an empty string ("") to use the default contract name.
/// </param>
/// <returns>
/// The <see cref="Lazy{T, TMetadataView}"/> object with the specified contract name.
/// </returns>
/// <remarks>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero <see cref="Lazy{T, TMetadataView}"/> objects with the
/// specified contract name in the <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one <see cref="Lazy{T, TMetadataView}"/> objects with the
/// specified contract name in the <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="InvalidOperationException">
/// <typeparamref name="TMetadataView"/> is not a valid metadata view type.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public Lazy<T, TMetadataView>? GetExport<T, TMetadataView>(string? contractName)
{
return GetExportCore<T, TMetadataView>(contractName);
}
/// <summary>
/// Returns the exports with the specified contract name.
/// </summary>
/// <param name="type">
/// The <see cref="Type"/> of the <see cref="Export"/> objects to return.
/// </param>
/// <param name="metadataViewType">
/// The <see cref="Type"/> of the metadata view of the <see cref="Export"/> objects to
/// return.
/// </param>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the
/// <see cref="Export"/> object to return; or <see langword="null"/>
/// or an empty string ("") to use the default contract name.
/// </param>
/// <returns>
/// An <see cref="IEnumerable{T}"/> containing the <see cref="Lazy{Object, Object}"/> objects
/// with the specified contract name, if found; otherwise, an empty
/// <see cref="IEnumerable{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The returned <see cref="Export"/> objects are instances of
/// <see cref="Lazy{T, TMetadataView}"/> underneath, where <c>T</c>
/// is <paramref name="type"/> and <c>TMetadataView</c> is
/// <paramref name="metadataViewType"/>.
/// </para>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <paramref name="type"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ArgumentNullException">
/// <paramref name="type"/> is <see langword="null"/>.
/// </exception>
/// <exception cref="InvalidOperationException">
/// <paramref name="metadataViewType"/> is not a valid metadata view type.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public IEnumerable<Lazy<object, object>> GetExports(Type type, Type? metadataViewType, string? contractName)
{
IEnumerable<Export> exports = GetExportsCore(type, metadataViewType, contractName, ImportCardinality.ZeroOrMore);
Collection<Lazy<object, object>> result = new Collection<Lazy<object, object>>();
Func<Export, Lazy<object, object>> typedExportFactory = ExportServices.CreateSemiStronglyTypedLazyFactory(type, metadataViewType);
foreach (Export export in exports)
{
result.Add(typedExportFactory.Invoke(export));
}
return result;
}
/// <summary>
/// Returns the exports with the contract name derived from the specified type parameter.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T}"/> objects to return. The contract name is also
/// derived from this type parameter.
/// </typeparam>
/// <returns>
/// An <see cref="IEnumerable{T}"/> containing the <see cref="Lazy{T}"/> objects
/// with the contract name derived from <typeparamref name="T"/>, if found; otherwise,
/// an empty <see cref="IEnumerable{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The returned <see cref="Lazy{T}"/> objects are instances of
/// <see cref="Lazy{T, TMetadataView}"/> underneath, where
/// <c>TMetadataView</c>
/// is <see cref="IDictionary{TKey, TValue}"/> and where <c>TKey</c>
/// is <see cref="string"/> and <c>TValue</c> is <see cref="object"/>.
/// </para>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public IEnumerable<Lazy<T>> GetExports<T>()
{
return GetExports<T>((string?)null);
}
/// <summary>
/// Returns the exports with the specified contract name.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T}"/> objects to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the <see cref="Lazy{T}"/>
/// objects to return; or <see langword="null"/> or an empty string ("") to use the
/// default contract name.
/// </param>
/// <returns>
/// An <see cref="IEnumerable{T}"/> containing the <see cref="Lazy{T}"/> objects
/// with the specified contract name, if found; otherwise, an empty
/// <see cref="IEnumerable{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The returned <see cref="Lazy{T}"/> objects are instances of
/// <see cref="Lazy{T, TMetadataView}"/> underneath, where
/// <c>TMetadataView</c>
/// is <see cref="IDictionary{TKey, TValue}"/> and where <c>TKey</c>
/// is <see cref="string"/> and <c>TValue</c> is <see cref="object"/>.
/// </para>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public IEnumerable<Lazy<T>> GetExports<T>(string? contractName)
{
return GetExportsCore<T>(contractName);
}
/// <summary>
/// Returns the exports with the contract name derived from the specified type parameter.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T, TMetadataView}"/> objects to return. The
/// contract name is also derived from this type parameter.
/// </typeparam>
/// <typeparam name="TMetadataView">
/// The type of the metadata view of the <see cref="Lazy{T, TMetadataView}"/> objects
/// to return.
/// </typeparam>
/// <returns>
/// An <see cref="IEnumerable{T}"/> containing the
/// <see cref="Lazy{T, TMetadataView}"/> objects with the contract name derived from
/// <typeparamref name="T"/>, if found; otherwise, an empty
/// <see cref="IEnumerable{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="InvalidOperationException">
/// <typeparamref name="TMetadataView"/> is not a valid metadata view type.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public IEnumerable<Lazy<T, TMetadataView>> GetExports<T, TMetadataView>()
{
return GetExports<T, TMetadataView>((string?)null);
}
/// <summary>
/// Returns the exports with the specified contract name.
/// </summary>
/// <typeparam name="T">
/// The type of the <see cref="Lazy{T, TMetadataView}"/> objects to return. The
/// contract name is also derived from this type parameter.
/// </typeparam>
/// <typeparam name="TMetadataView">
/// The type of the metadata view of the <see cref="Lazy{T, TMetadataView}"/> objects
/// to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the
/// <see cref="Lazy{T, TMetadataView}"/> objects to return; or <see langword="null"/>
/// or an empty string ("") to use the default contract name.
/// </param>
/// <returns>
/// An <see cref="IEnumerable{T}"/> containing the
/// <see cref="Lazy{T, TMetadataView}"/> objects with the specified contract name if
/// found; otherwise, an empty <see cref="IEnumerable{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="InvalidOperationException">
/// <typeparamref name="TMetadataView"/> is not a valid metadata view type.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
public IEnumerable<Lazy<T, TMetadataView>> GetExports<T, TMetadataView>(string? contractName)
{
return GetExportsCore<T, TMetadataView>(contractName);
}
/// <summary>
/// Returns the exported value with the contract name derived from the specified type
/// parameter, throwing an exception if there is not exactly one matching exported value.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return. The contract name is also
/// derived from this type parameter.
/// </typeparam>
/// <returns>
/// The exported <see cref="object"/> with the contract name derived from
/// <typeparamref name="T"/>.
/// </returns>
/// <remarks>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// The underlying exported value cannot be cast to <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero exported values with the contract name derived from
/// <typeparamref name="T"/> in the <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one exported values with the contract name derived from
/// <typeparamref name="T"/> in the <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public T? GetExportedValue<T>()
{
return GetExportedValue<T>((string?)null);
}
/// <summary>
/// Returns the exported value with the specified contract name, throwing an exception
/// if there is not exactly one matching exported value.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the exported value to return,
/// or <see langword="null"/> or an empty string ("") to use the default contract name.
/// </param>
/// <returns>
/// The exported <see cref="object"/> with the specified contract name.
/// </returns>
/// <remarks>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// The underlying exported value cannot be cast to <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are zero exported values with the specified contract name in the
/// <see cref="CompositionContainer"/>.
/// </para>
/// -or-
/// <para>
/// There are more than one exported values with the specified contract name in the
/// <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public T? GetExportedValue<T>(string? contractName)
{
return GetExportedValueCore<T>(contractName, ImportCardinality.ExactlyOne);
}
/// <summary>
/// Returns the exported value with the contract name derived from the specified type
/// parameter, throwing an exception if there is more than one matching exported value.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return. The contract name is also
/// derived from this type parameter.
/// </typeparam>
/// <returns>
/// The exported <see cref="object"/> with the contract name derived from
/// <typeparamref name="T"/>, if found; otherwise, the default value for
/// <typeparamref name="T"/>.
/// </returns>
/// <remarks>
/// <para>
/// If the exported value is not found, then this method returns the appropriate
/// default value for <typeparamref name="T"/>; for example, 0 (zero) for integer
/// types, <see langword="false"/> for Boolean types, and <see langword="null"/>
/// for reference types.
/// </para>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// The underlying exported value cannot be cast to <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ImportCardinalityMismatchException">
/// <para>
/// There are more than one exported values with the contract name derived from
/// <typeparamref name="T"/> in the <see cref="CompositionContainer"/>.
/// </para>
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public T? GetExportedValueOrDefault<T>()
{
return GetExportedValueOrDefault<T>((string?)null);
}
/// <summary>
/// Returns the exported value with the specified contract name, throwing an exception
/// if there is more than one matching exported value.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the exported value to return,
/// or <see langword="null"/> or an empty string ("") to use the default contract name.
/// </param>
/// <returns>
/// The exported <see cref="object"/> with the specified contract name, if found;
/// otherwise, the default value for <typeparamref name="T"/>.
/// </returns>
/// <remarks>
/// <para>
/// If the exported value is not found, then this method returns the appropriate
/// default value for <typeparamref name="T"/>; for example, 0 (zero) for integer
/// types, <see langword="false"/> for Boolean types, and <see langword="null"/>
/// for reference types.
/// </para>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// The underlying exported value cannot be cast to <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ImportCardinalityMismatchException">
/// There are more than one exported values with the specified contract name in the
/// <see cref="CompositionContainer"/>.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public T? GetExportedValueOrDefault<T>(string? contractName)
{
return GetExportedValueCore<T>(contractName, ImportCardinality.ZeroOrOne);
}
/// <summary>
/// Returns the exported values with the contract name derived from the specified type
/// parameter.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return. The contract name is also
/// derived from this type parameter.
/// </typeparam>
/// <returns>
/// An <see cref="Collection{T}"/> containing the exported values with the contract name
/// derived from the specified type parameter, if found; otherwise, an empty
/// <see cref="Collection{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// One or more of the underlying exported values cannot be cast to
/// <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public IEnumerable<T> GetExportedValues<T>()
{
return GetExportedValues<T>((string?)null);
}
/// <summary>
/// Returns the exported values with the specified contract name.
/// </summary>
/// <typeparam name="T">
/// The type of the exported value to return.
/// </typeparam>
/// <param name="contractName">
/// A <see cref="string"/> containing the contract name of the exported values to
/// return; or <see langword="null"/> or an empty string ("") to use the default
/// contract name.
/// </param>
/// <returns>
/// An <see cref="Collection{T}"/> containing the exported values with the specified
/// contract name, if found; otherwise, an empty <see cref="Collection{T}"/>.
/// </returns>
/// <remarks>
/// <para>
/// The default contract name is the result of calling
/// <see cref="AttributedModelServices.GetContractName(Type)"/> on <typeparamref name="T"/>.
/// </para>
/// <para>
/// The contract name is compared using a case-sensitive, non-linguistic comparison
/// using <see cref="StringComparer.Ordinal"/>.
/// </para>
/// </remarks>
/// <exception cref="CompositionContractMismatchException">
/// One or more of the underlying exported values cannot be cast to
/// <typeparamref name="T"/>.
/// </exception>
/// <exception cref="ObjectDisposedException">
/// The <see cref="CompositionContainer"/> has been disposed of.
/// </exception>
/// <exception cref="CompositionException">
/// An error occurred during composition. <see cref="CompositionException.Errors"/> will
/// contain a collection of errors that occurred.
/// </exception>
public IEnumerable<T> GetExportedValues<T>(string? contractName)
{
return GetExportedValuesCore<T>(contractName);
}
private Collection<T> GetExportedValuesCore<T>(string? contractName)
{
IEnumerable<Export> exports = GetExportsCore(typeof(T), (Type?)null, contractName, ImportCardinality.ZeroOrMore);
Collection<T> result = new Collection<T>();
foreach (Export export in exports)
{
result.Add(ExportServices.GetCastedExportedValue<T>(export));
}
return result;
}
private T? GetExportedValueCore<T>(string? contractName, ImportCardinality cardinality)
{
if (!cardinality.IsAtMostOne())
{
throw new Exception(SR.Diagnostic_InternalExceptionMessage);
}
Export? export = GetExportsCore(typeof(T), (Type?)null, contractName, cardinality).SingleOrDefault();
return (export != null) ? ExportServices.GetCastedExportedValue<T>(export) : default;
}
private Collection<Lazy<T>> GetExportsCore<T>(string? contractName)
{
IEnumerable<Export> exports = GetExportsCore(typeof(T), (Type?)null, contractName, ImportCardinality.ZeroOrMore);
Collection<Lazy<T>> result = new Collection<Lazy<T>>();
foreach (Export export in exports)
{
result.Add(ExportServices.CreateStronglyTypedLazyOfT<T>(export));
}
return result;
}
private Collection<Lazy<T, TMetadataView>> GetExportsCore<T, TMetadataView>(string? contractName)
{
IEnumerable<Export> exports = GetExportsCore(typeof(T), typeof(TMetadataView), contractName, ImportCardinality.ZeroOrMore);
Collection<Lazy<T, TMetadataView>> result = new Collection<Lazy<T, TMetadataView>>();
foreach (Export export in exports)
{
result.Add(ExportServices.CreateStronglyTypedLazyOfTM<T, TMetadataView>(export));
}
return result;
}
private Lazy<T, TMetadataView>? GetExportCore<T, TMetadataView>(string? contractName)
{
Export? export = GetExportsCore(typeof(T), typeof(TMetadataView), contractName, ImportCardinality.ExactlyOne).SingleOrDefault();
return (export != null) ? ExportServices.CreateStronglyTypedLazyOfTM<T, TMetadataView>(export) : null;
}
private Lazy<T>? GetExportCore<T>(string? contractName)
{
Export? export = GetExportsCore(typeof(T), null, contractName, ImportCardinality.ExactlyOne).SingleOrDefault();
return (export != null) ? ExportServices.CreateStronglyTypedLazyOfT<T>(export) : null;
}
private IEnumerable<Export> GetExportsCore(Type type, Type? metadataViewType, string? contractName, ImportCardinality cardinality)
{
// Only 'type' cannot be null - the other parameters have sensible defaults.
Requires.NotNull(type, nameof(type));
if (string.IsNullOrEmpty(contractName))
{
contractName = AttributedModelServices.GetContractName(type);
}
metadataViewType ??= ExportServices.DefaultMetadataViewType;
if (!MetadataViewProvider.IsViewTypeValid(metadataViewType))
{
throw new InvalidOperationException(SR.Format(SR.InvalidMetadataView, metadataViewType.Name));
}
ContractBasedImportDefinition importDefinition = BuildImportDefinition(type, metadataViewType, contractName, cardinality);
return GetExports(importDefinition, null);
}
private static ContractBasedImportDefinition BuildImportDefinition(Type type, Type metadataViewType, string contractName, ImportCardinality cardinality)
{
ArgumentNullException.ThrowIfNull(type);
ArgumentNullException.ThrowIfNull(metadataViewType);
ArgumentNullException.ThrowIfNull(contractName);
IEnumerable<KeyValuePair<string, Type>> requiredMetadata = CompositionServices.GetRequiredMetadata(metadataViewType);
IDictionary<string, object?> metadata = CompositionServices.GetImportMetadata(type, null);
string? requiredTypeIdentity = null;
if (type != typeof(object))
{
requiredTypeIdentity = AttributedModelServices.GetTypeIdentity(type);
}
return new ContractBasedImportDefinition(contractName, requiredTypeIdentity, requiredMetadata, cardinality, false, true, CreationPolicy.Any, metadata);
}
}
}
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