The IPackagePart conforms fully to the ECMA TC45 Open Packaging Conventions.

The package implementer shall require a content type that does not include comments and the format designer shall specify such a content type. [M1.15]

IPackage implementers shall only create and only recognize parts with a content type; format designers shall specify a content type for each part included in the format. Content types for package parts shall fit the definition and syntax for media types as specified in RFC 2616, §3.7. [M1.13]

Content types shall not use linear white space either between the type and subtype or between an attribute and its value. Content types also shall not have leading or trailing white spaces. IPackage implementers shall create only such content types and shall require such content types when retrieving a part from a package; format designers shall specify only such content types for inclusion in the format. [M1.14]

IPackage implementers and format designers shall not create content types with parameters for the package specific parts defined in this Open Packaging specification and shall treat the presence of parameters in these content types as an error. [M1.22]

The package implementer shall require a content type and the format designer shall specify the content type. [M1.2], [M1.13]

The IPackage.GetPart method threw an exception.

Part name equivalence is determined by comparing part names as case-insensitive ASCII strings. Packages shall not contain equivalent part names and package implementers shall neither create nor recognize packages with equivalent part names. [M1.12]

If the package implementer specifies a growth hint, it is set when a part is created and the package implementer shall not change the growth hint after the part has been created. [M1.16]

A package implementer shall neither create nor recognize a part with a part name derived from another part name by appending segments to it. [M1.11]

A part name shall start with a forward slash (“/”) character. [M1.4]

A part name shall not have a forward slash as the last character. [M1.5]

The package implementer shall require a part name. [M1.1]

The package implementer shall require that every Relationship element has an Id attribute, the value of which is unique within the Relationships part, and that the Id type is xsd:ID, the value of which conforms to the naming restrictions for xsd:IDas described in the W3C Recommendation “XML Schema Part 2: Datatypes.” [M1.26]

The package implementer shall name relationship parts according to the special relationships part naming convention and require that parts with names that conform to this naming convention have the content type for a Relationships part. [M1.30]

The package implementer shall require the Target attribute to be a URI reference pointing to a target resource. The URI reference shall be a URI or a relative reference. [M1.28]

When set to Internal, the Target attribute shall be a relative reference and that reference is interpreted relative to the “parent” part. For package relationships, the package implementer shallresolve relative references in the Target attribute against the pack URI that identifies the entire package resource. [M1.29]

The Relationships part shall not have relationships to any other part. IPackage implementers shall enforce this requirement upon the attempt to create such a relationship and shall treat any such relationship as invalid. [M1.25]

The package implementer shall require the Type attribute to be a URI that defines the role of the relationship and the format designer shall specify such a Type. [M1.27]

A part name shall not have empty segments. [M1.3]

A segment shall not end with a dot (“.”) character. [M1.9]

A segment shall not hold any characters other than pchar characters. [M1.6]

A segment shall not contain percent-encoded forward slash (“/”), or backward slash (“\”) characters. [M1.7]

A segment shall not contain percent-encoded unreserved characters. [M1.8]

A segment shall include at least one non-dot character. [M1.10]

XML content shall not contain elements or attributes drawn from “xml” or “xsi” namespaces unless they are explicitly defined in the XSD schema or by other means described in this Open Packaging specification. IPackage implementers shall enforce this requirement upon creation and retrieval of the XML content. [M1.21]

XML content shall be valid against the corresponding XSD schema defined in this Open Packaging specification. In particular, the XML content shall not contain elements or attributes drawn from namespaces that are not explicitly defined in the corresponding XSD unless the XSD allows elements or attributes drawn from any namespace to be present in particular locations in the XML markup. IPackage implementers shall enforce this requirement upon creation and retrieval of the XML content. [M1.20]

XML content shall be encoded using either UTF-8 or UTF-16. If any part includes an encoding declaration, as defined in §4.3.3 of the XML 1.0 specification, that declaration shall not name any encoding other than UTF-8 or UTF-16. IPackage implementers shall enforce this requirement upon creation and retrieval of the XML content. [M1.17]