XDocumentType.SystemId Proprietà

Definizione

Spazio dei nomi:

System.Xml.Linq

Assembly:

System.Xml.XDocument.dll

Assembly:

System.Xml.Linq.dll

Assembly:

netstandard.dll

Ottiene o imposta l'identificatore di sistema per questa definizione DTD (Document Type Definition).

public:
 property System::String ^ SystemId { System::String ^ get(); void set(System::String ^ value); };

public string SystemId { get; set; }

public string? SystemId { get; set; }

member this.SystemId : string with get, set

Public Property SystemId As String

Valore della proprietà

String

String che contiene l'identificatore di sistema per questa definizione DTD (Document Type Definition).

Esempio

Nell'esempio seguente viene creato un documento XML che fa riferimento a un DTD privato esterno. Il DTD non dispone di un subset interno. La chiamata al XDocumentType costruttore riflette l'uso del DTD privato esterno. Passa null per il subset interno.

string pubsDtd =  
@"<!ELEMENT Pubs (Book+)>  
<!ELEMENT Book (Title, Author)>  
<!ELEMENT Title (#PCDATA)>  
<!ELEMENT Author (#PCDATA)>";  
File.WriteAllText("Pubs.dtd", pubsDtd);  

string target = "xml-stylesheet";  
string data = "href=\"mystyle.css\" title=\"Compact\" type=\"text/css\"";  

XDocument doc = new XDocument(  
    new XDocumentType("Pubs", null, "Pubs.dtd", null),  
    new XElement("Pubs",   
        new XElement("Book",  
            new XElement("Title", "Artifacts of Roman Civilization"),  
            new XElement("Author", "Moreno, Jordao")  
        ),  
        new XElement("Book",  
            new XElement("Title", "Midieval Tools and Implements"),  
            new XElement("Author", "Gazit, Inbar")  
        )  
    ),  
    new XComment("This is another comment.")  
);  
doc.Declaration = new XDeclaration("1.0", "utf-8", "true");  
doc.Save("Pubs.xml");  

// Validate Pubs.xml against Pubs.dtd.  
XmlReaderSettings xrs = new XmlReaderSettings();  
xrs.ProhibitDtd = false;  
xrs.ValidationType = ValidationType.DTD;  
xrs.ConformanceLevel = ConformanceLevel.Auto;  
XmlReader xr = XmlReader.Create("Pubs.xml", xrs);  
XDocument doc2 = XDocument.Load(xr);  

XDocumentType dt = doc2.Document.DocumentType;  
Console.WriteLine("SystemId:{0}", dt.SystemId);  

Dim pubsDtd As String = _   
    "<!ELEMENT Pubs (Book+)>" & Environment.NewLine & _  
    "<!ELEMENT Book (Title, Author)>" & Environment.NewLine & _  
    "<!ELEMENT Title (#PCDATA)>" & Environment.NewLine & _  
    "<!ELEMENT Author (#PCDATA)>"  
File.WriteAllText("Pubs.dtd", pubsDtd)  

Dim target As String = "xml-stylesheet"  
Dim data As String = "href='mystyle.css' title='Compact' type='text/css'"  

Dim doc As XDocument = _  
    <?xml version='1.0'?>  
    <Pubs>  
        <Book>  
            <Title>Artifacts of Roman Civilization</Title>  
            <Author>Moreno, Jordao</Author>  
        </Book>  
        <Book>  
            <Title>Midieval Tools and Implements</Title>  
            <Author>Gazit, Inbar</Author>  
        </Book>  
    </Pubs>  
    <!--This is another comment.-->  

doc _  
.FirstNode _  
.AddBeforeSelf(New XDocumentType("Pubs", Nothing, "Pubs.dtd", Nothing))  

doc.Declaration = New XDeclaration("1.0", "utf-8", "true")  
doc.Save("Pubs.xml")  

' Validate Pubs.xml against Pubs.dtd.  
Dim xrs As XmlReaderSettings = New XmlReaderSettings()  
xrs.ProhibitDtd = False  
xrs.ValidationType = ValidationType.DTD  
xrs.ConformanceLevel = ConformanceLevel.Auto  
Dim xr As XmlReader = XmlReader.Create("Pubs.xml", xrs)  
Dim doc2 As XDocument = XDocument.Load(xr)  

Dim dt As XDocumentType = doc2.Document.DocumentType  
Console.WriteLine("SystemId:{0}", dt.SystemId)  

Nell'esempio viene prodotto l'output seguente:

SystemId:Pubs.dtd  

Commenti

Se un documento XML utilizza un DTD privato esterno, questa proprietà conterrà l'identificatore privato del DTD esterno.

Vedi anche

• Panoramica di LINQ to XML