Package.GetRelationshipsByType(String) Package.GetRelationshipsByType(String) Package.GetRelationshipsByType(String) Package.GetRelationshipsByType(String) Method

Definition

Returns a collection of all the package-level relationships that match a given RelationshipType.

public:
 System::IO::Packaging::PackageRelationshipCollection ^ GetRelationshipsByType(System::String ^ relationshipType);
public System.IO.Packaging.PackageRelationshipCollection GetRelationshipsByType (string relationshipType);
member this.GetRelationshipsByType : string -> System.IO.Packaging.PackageRelationshipCollection
Public Function GetRelationshipsByType (relationshipType As String) As PackageRelationshipCollection

Parameters

relationshipType
String String String String

The RelationshipType to match and return in the collection.

Returns

A collection of package-level relationships that match the specified relationshipType.

Exceptions

The package is write-only.

Examples

The following example shows how to retrieve the relationships that have been defined for the package. For the complete sample, see Reading a Package Sample.

// Open the Package.
// ('using' statement insures that 'package' is
//  closed and disposed when it goes out of scope.)
using (Package package =
    Package.Open(packagePath, FileMode.Open, FileAccess.Read))
{
    PackagePart documentPart = null;
    PackagePart resourcePart = null;

    // Get the Package Relationships and look for
    //   the Document part based on the RelationshipType
    Uri uriDocumentTarget = null;
    foreach (PackageRelationship relationship in
        package.GetRelationshipsByType(PackageRelationshipType))
    {
        // Resolve the Relationship Target Uri
        //   so the Document Part can be retrieved.
        uriDocumentTarget = PackUriHelper.ResolvePartUri(
            new Uri("/", UriKind.Relative), relationship.TargetUri);

        // Open the Document Part, write the contents to a file.
        documentPart = package.GetPart(uriDocumentTarget);
        ExtractPart(documentPart, targetDirectory);
    }

    // Get the Document part's Relationships,
    //   and look for required resources.
    Uri uriResourceTarget = null;
    foreach (PackageRelationship relationship in
        documentPart.GetRelationshipsByType(
                                ResourceRelationshipType))
    {
        // Resolve the Relationship Target Uri
        //   so the Resource Part can be retrieved.
        uriResourceTarget = PackUriHelper.ResolvePartUri(
            documentPart.Uri, relationship.TargetUri);

        // Open the Resource Part and write the contents to a file.
        resourcePart = package.GetPart(uriResourceTarget);
        ExtractPart(resourcePart, targetDirectory);
    }

}// end:using(Package package) - Close & dispose package.
' Open the Package.
' ('using' statement insures that 'package' is
'  closed and disposed when it goes out of scope.)
Using package As Package = Package.Open(packagePath, FileMode.Open, FileAccess.Read)
    Dim documentPart As PackagePart = Nothing
    Dim resourcePart As PackagePart = Nothing

    ' Get the Package Relationships and look for
    '   the Document part based on the RelationshipType
    Dim uriDocumentTarget As Uri = Nothing
    For Each relationship As PackageRelationship In package.GetRelationshipsByType(PackageRelationshipType)
        ' Resolve the Relationship Target Uri
        '   so the Document Part can be retrieved.
        uriDocumentTarget = PackUriHelper.ResolvePartUri(New Uri("/", UriKind.Relative), relationship.TargetUri)

        ' Open the Document Part, write the contents to a file.
        documentPart = package.GetPart(uriDocumentTarget)
        ExtractPart(documentPart, targetDirectory)
    Next relationship

    ' Get the Document part's Relationships,
    '   and look for required resources.
    Dim uriResourceTarget As Uri = Nothing
    For Each relationship As PackageRelationship In documentPart.GetRelationshipsByType(ResourceRelationshipType)
        ' Resolve the Relationship Target Uri
        '   so the Resource Part can be retrieved.
        uriResourceTarget = PackUriHelper.ResolvePartUri(documentPart.Uri, relationship.TargetUri)

        ' Open the Resource Part and write the contents to a file.
        resourcePart = package.GetPart(uriResourceTarget)
        ExtractPart(resourcePart, targetDirectory)
    Next relationship

End Using ' end:using(Package package) - Close & dispose package.

Remarks

GetRelationships will never return null; however the returned collection may contain zero elements if there are no package-level relationships that match the specified relationshipType.

The following table shows the package-level relationshipType URIs defined by the Open Packaging Conventions (OPC) specification.

Package-level Relationship Relationship Type URI
Core Properties http://schemas.openxmlformats.org/package/2006/relationships/metadata/core-properties
Digital Signature http://schemas.openxmlformats.org/package/2006/relationships/digital-signature/signature
Digital Signature Certificate http://schemas.openxmlformats.org/package/2006/relationships/digital-signature/certificate
Digital Signature Origin http://schemas.openxmlformats.org/package/2006/relationships/digital-signature/origin
Thumbnail http://schemas.openxmlformats.org/package/2006/relationships/metadata/thumbnail

For additional information, see the Open Packaging Conventions (OPC) specification available for download at https://go.microsoft.com/fwlink/?LinkID=71255.

Applies to

See also