Package.GetPart(Uri) 方法

定义

命名空间:

System.IO.Packaging

程序集:

System.IO.Packaging.dll

包:

System.IO.Packaging v8.0.0

Source:

Package.cs

返回具有给定 URI 的部件。

public:
 System::IO::Packaging::PackagePart ^ GetPart(Uri ^ partUri);

public System.IO.Packaging.PackagePart GetPart (Uri partUri);

member this.GetPart : Uri -> System.IO.Packaging.PackagePart

Public Function GetPart (partUri As Uri) As PackagePart

参数

partUri

Uri

要返回的部件的统一资源标识符 (URI)。

返回

PackagePart

具有指定 partUri 的部件。

例外

ArgumentNullException

partUri 为 null。

ArgumentException

partUri 不是有效的 PackagePart 统一资源标识符 (URI)。

InvalidOperationException

包中不存在具有指定 partUri 的部件。

ObjectDisposedException

包未打开（已调用了 Dispose(Boolean) 或 Close()）。

IOException

包是只写的。

示例

以下示例演示如何查找、检索和读取包中包含的部件。 有关完整示例，请参阅 读取包示例。

// 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.

注解

InvalidOperationException如果具有指定 partUri 的部件不存在，则会引发 。

方法 PartExists 可用于确定是否 partUri 引用现有部件。

默认情况下， ZipPackage 提供并使用抽象 Package 基类的派生实现。 在默认操作中， GetPart 在内部调用 GetPartCoreZipPackage 类以从 ZIP 文件返回请求的部件。

有关其他信息，请参阅开放打包约定 (OPC) 规范，可从 下载 https://www.ecma-international.org/publications-and-standards/standards/ecma-376/。

继承者说明

GetPart(Uri) 在内部调用派生类方法，根据派生类 GetPartCore(Uri) 中实现的物理格式实际刷新部件。

另请参阅

• GetParts()
• PartExists(Uri)
• CreatePartUri(Uri)
• GetPartUri(Uri)
• ResolvePartUri(Uri, Uri)