XPathNavigator.SelectSingleNode 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
於 XPathNavigator 中選取單一節點。
多載
SelectSingleNode(String, IXmlNamespaceResolver) |
使用指定的 XPath 查詢並搭配指定的 XPathNavigator 物件,在 IXmlNamespaceResolver 物件中選取單一節點,以解析命名空間前置詞。 |
SelectSingleNode(String) |
使用指定的 XPath 查詢,於 XPathNavigator 中選取單一節點。 |
SelectSingleNode(XPathExpression) |
使用指定的 XPathNavigator 物件,於 XPathExpression 中選取單一節點。 |
SelectSingleNode(String, IXmlNamespaceResolver)
使用指定的 XPath 查詢並搭配指定的 XPathNavigator 物件,在 IXmlNamespaceResolver 物件中選取單一節點,以解析命名空間前置詞。
public:
virtual System::Xml::XPath::XPathNavigator ^ SelectSingleNode(System::String ^ xpath, System::Xml::IXmlNamespaceResolver ^ resolver);
public virtual System.Xml.XPath.XPathNavigator? SelectSingleNode (string xpath, System.Xml.IXmlNamespaceResolver? resolver);
public virtual System.Xml.XPath.XPathNavigator SelectSingleNode (string xpath, System.Xml.IXmlNamespaceResolver resolver);
abstract member SelectSingleNode : string * System.Xml.IXmlNamespaceResolver -> System.Xml.XPath.XPathNavigator
override this.SelectSingleNode : string * System.Xml.IXmlNamespaceResolver -> System.Xml.XPath.XPathNavigator
Public Overridable Function SelectSingleNode (xpath As String, resolver As IXmlNamespaceResolver) As XPathNavigator
參數
- resolver
- IXmlNamespaceResolver
IXmlNamespaceResolver 物件,用來解析 XPath 查詢中的命名空間前置詞。
傳回
XPathNavigator 物件,包含指定 XPath 查詢的第一個相符節點;如果沒有查詢結果,則為 null
例外狀況
在 XPath 查詢中遇到了錯誤,或是 XPath 運算式的傳回型別不是節點。
XPath 查詢無效。
範例
下列範例會根據指定的 XPath 查詢,從 XPathNavigator 物件中選取單一節點,並使用 XmlNamespaceManager 指定的 物件解析 XPath 查詢中的命名空間前置詞。
XPathDocument^ document = gcnew XPathDocument("contosoBooks.xml");
XPathNavigator^ navigator = document->CreateNavigator();
XmlNamespaceManager^ manager = gcnew XmlNamespaceManager(navigator->NameTable);
manager->AddNamespace("bk", "http://www.contoso.com/books");
XPathNavigator^ node = navigator->SelectSingleNode("//bk:title", manager);
Console::WriteLine(node->InnerXml);
XPathDocument document = new XPathDocument("contosoBooks.xml");
XPathNavigator navigator = document.CreateNavigator();
XmlNamespaceManager manager = new XmlNamespaceManager(navigator.NameTable);
manager.AddNamespace("bk", "http://www.contoso.com/books");
XPathNavigator node = navigator.SelectSingleNode("//bk:title", manager);
Console.WriteLine(node.InnerXml);
Dim document As XPathDocument = New XPathDocument("contosoBooks.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()
Dim manager As XmlNamespaceManager = New XmlNamespaceManager(navigator.NameTable)
manager.AddNamespace("bk", "http://www.contoso.com/books")
Dim node As XPathNavigator = navigator.SelectSingleNode("//bk:title", manager)
Console.WriteLine(node.InnerXml)
範例將 contosoBooks.xml
檔案做為輸入。
<?xml version="1.0" encoding="utf-8" ?>
<bookstore xmlns="http://www.contoso.com/books">
<book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">
<title>The Autobiography of Benjamin Franklin</title>
<author>
<first-name>Benjamin</first-name>
<last-name>Franklin</last-name>
</author>
<price>8.99</price>
</book>
<book genre="novel" publicationdate="1967-11-17" ISBN="0-201-63361-2">
<title>The Confidence Man</title>
<author>
<first-name>Herman</first-name>
<last-name>Melville</last-name>
</author>
<price>11.99</price>
</book>
<book genre="philosophy" publicationdate="1991-02-15" ISBN="1-861001-57-6">
<title>The Gorgias</title>
<author>
<name>Plato</name>
</author>
<price>9.99</price>
</book>
</bookstore>
備註
方法 SelectSingleNode 會選取符合指定 XPath 查詢的第一個節點。 方法 SelectSingleNode 會 IXmlNamespaceResolver 使用 物件來解析命名空間前置詞。
注意
在 XPath 中,所有命名空間都必須在查詢中加上前置詞。 如果 XML 檔使用預設命名空間,您仍必須將命名空間前置詞新增至 IXmlNamespaceResolver 物件。
適用於
SelectSingleNode(String)
使用指定的 XPath 查詢,於 XPathNavigator 中選取單一節點。
public:
virtual System::Xml::XPath::XPathNavigator ^ SelectSingleNode(System::String ^ xpath);
public virtual System.Xml.XPath.XPathNavigator? SelectSingleNode (string xpath);
public virtual System.Xml.XPath.XPathNavigator SelectSingleNode (string xpath);
abstract member SelectSingleNode : string -> System.Xml.XPath.XPathNavigator
override this.SelectSingleNode : string -> System.Xml.XPath.XPathNavigator
Public Overridable Function SelectSingleNode (xpath As String) As XPathNavigator
參數
傳回
XPathNavigator 物件,包含指定 XPath 查詢的第一個相符節點;如果沒有查詢結果,則為 null
例外狀況
在 XPath 查詢中遇到了錯誤,或是 XPath 運算式的傳回型別不是節點。
XPath 查詢無效。
範例
下列範例會根據指定的 XPath 查詢,從 XPathNavigator 中選取單一節點。
XPathDocument^ document = gcnew XPathDocument("books.xml");
XPathNavigator^ navigator = document->CreateNavigator();
XPathNavigator^ node = navigator->SelectSingleNode("//title");
Console::WriteLine(node->InnerXml);
XPathDocument document = new XPathDocument("books.xml");
XPathNavigator navigator = document.CreateNavigator();
XPathNavigator node = navigator.SelectSingleNode("//title");
Console.WriteLine(node.InnerXml);
Dim document As XPathDocument = New XPathDocument("books.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()
Dim node As XPathNavigator = navigator.SelectSingleNode("//title")
Console.WriteLine(node.InnerXml)
範例將 books.xml
檔案做為輸入。
<?xml version="1.0" encoding="utf-8" ?>
<bookstore>
<book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">
<title>The Autobiography of Benjamin Franklin</title>
<author>
<first-name>Benjamin</first-name>
<last-name>Franklin</last-name>
</author>
<price>8.99</price>
</book>
<book genre="novel" publicationdate="1967-11-17" ISBN="0-201-63361-2">
<title>The Confidence Man</title>
<author>
<first-name>Herman</first-name>
<last-name>Melville</last-name>
</author>
<price>11.99</price>
</book>
<book genre="philosophy" publicationdate="1991-02-15" ISBN="1-861001-57-6">
<title>The Gorgias</title>
<author>
<name>Plato</name>
</author>
<price>9.99</price>
</book>
</bookstore>
備註
方法 SelectSingleNode 會選取符合 物件中 XPathNavigator XPath 查詢的第一個節點。
適用於
SelectSingleNode(XPathExpression)
使用指定的 XPathNavigator 物件,於 XPathExpression 中選取單一節點。
public:
virtual System::Xml::XPath::XPathNavigator ^ SelectSingleNode(System::Xml::XPath::XPathExpression ^ expression);
public virtual System.Xml.XPath.XPathNavigator? SelectSingleNode (System.Xml.XPath.XPathExpression expression);
public virtual System.Xml.XPath.XPathNavigator SelectSingleNode (System.Xml.XPath.XPathExpression expression);
abstract member SelectSingleNode : System.Xml.XPath.XPathExpression -> System.Xml.XPath.XPathNavigator
override this.SelectSingleNode : System.Xml.XPath.XPathExpression -> System.Xml.XPath.XPathNavigator
Public Overridable Function SelectSingleNode (expression As XPathExpression) As XPathNavigator
參數
- expression
- XPathExpression
包含已編譯 XPath 查詢的 XPathExpression 物件。
傳回
XPathNavigator 物件,包含指定 XPath 查詢的第一個相符節點;如果沒有查詢結果,則為 null
例外狀況
在 XPath 查詢中遇到了錯誤,或是 XPath 運算式的傳回型別不是節點。
XPath 查詢無效。
範例
下列範例會根據 中包含的 XPathExpression XPath 查詢,從 XPathNavigator 中選取單一節點。
XPathDocument^ document = gcnew XPathDocument("books.xml");
XPathNavigator^ navigator = document->CreateNavigator();
XPathExpression^ query = navigator->Compile("//title");
XPathNavigator^ node = navigator->SelectSingleNode(query);
Console::WriteLine(node->InnerXml);
XPathDocument document = new XPathDocument("books.xml");
XPathNavigator navigator = document.CreateNavigator();
XPathExpression query = navigator.Compile("//title");
XPathNavigator node = navigator.SelectSingleNode(query);
Console.WriteLine(node.InnerXml);
Dim document As XPathDocument = New XPathDocument("books.xml")
Dim navigator As XPathNavigator = document.CreateNavigator()
Dim query As XPathExpression = navigator.Compile("//title")
Dim node As XPathNavigator = navigator.SelectSingleNode(query)
Console.WriteLine(node.InnerXml)
範例將 books.xml
檔案做為輸入。
<?xml version="1.0" encoding="utf-8" ?>
<bookstore>
<book genre="autobiography" publicationdate="1981-03-22" ISBN="1-861003-11-0">
<title>The Autobiography of Benjamin Franklin</title>
<author>
<first-name>Benjamin</first-name>
<last-name>Franklin</last-name>
</author>
<price>8.99</price>
</book>
<book genre="novel" publicationdate="1967-11-17" ISBN="0-201-63361-2">
<title>The Confidence Man</title>
<author>
<first-name>Herman</first-name>
<last-name>Melville</last-name>
</author>
<price>11.99</price>
</book>
<book genre="philosophy" publicationdate="1991-02-15" ISBN="1-861001-57-6">
<title>The Gorgias</title>
<author>
<name>Plato</name>
</author>
<price>9.99</price>
</book>
</bookstore>
備註
方法 SelectSingleNode 會選取符合 物件中所 XPathExpressionXPathNavigator 包含編譯 XPath 查詢的第一個節點。