搭配使用內嵌 XML 結構描述與 XmlReader 進行驗證

更新： November 2007

您可以根據內嵌 XML 結構描述定義語言 (XSD) 結構描述驗證 XML 檔案。建立 XmlReader 之前，請變更 XmlReaderSettings.ValidationFlags 屬性以啟用 ProcessInlineSchema 選項。

注意事項：
由於內嵌結構描述是以根項目的項目子系出現，因此當執行內嵌結構描述驗證時，無法驗證根項目。並且會針對根項目產生驗證警告。

範例

下列範例會使用內嵌 XML 結構描述驗證 XML 檔案。因為讀取器已設定為必須顯示驗證警告，所以您還會在根項目上看到預期的警告。

Imports System
Imports System.Xml
Imports System.Xml.Schema
Imports System.IO

public class ValidXSD 

  public shared sub Main() 

    ' Set the validation settings.
    Dim settings as XmlReaderSettings = new XmlReaderSettings()
    settings.ValidationType = ValidationType.Schema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ProcessInlineSchema
    settings.ValidationFlags = settings.ValidationFlags Or XmlSchemaValidationFlags.ReportValidationWarnings
      AddHandler settings.ValidationEventHandler, AddressOf ValidationCallBack

    ' Create the XmlReader object.
    Dim reader as XmlReader = XmlReader.Create("inlineSchema.xml", settings)

    ' Parse the file. 
    while (reader.Read())
    end while
  end sub

  ' Display any warnings or errors.
  private shared sub ValidationCallBack (sender as object, args as ValidationEventArgs)
     if (args.Severity=XmlSeverityType.Warning)
       Console.WriteLine("   Warning: Matching schema not found.  No validation occurred." + args.Message)
     else
        Console.WriteLine("   Validation error: " + args.Message)
     end if
  end sub 

end class 

using System;
using System.Xml;
using System.Xml.Schema;
using System.IO;

public class ValidXSD {

  public static void Main() {

    // Set the validation settings.
    XmlReaderSettings settings = new XmlReaderSettings();
    settings.ValidationType = ValidationType.Schema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessInlineSchema;
    settings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
    settings.ValidationEventHandler += new ValidationEventHandler (ValidationCallBack);

    // Create the XmlReader object.
    XmlReader reader = XmlReader.Create("inlineSchema.xml", settings);

    // Parse the file. 
    while (reader.Read());

  }

  // Display any warnings or errors.
  private static void ValidationCallBack (object sender, ValidationEventArgs args) {
     if (args.Severity==XmlSeverityType.Warning)
       Console.WriteLine("\tWarning: Matching schema not found.  No validation occurred." + args.Message);
     else
        Console.WriteLine("\tValidation error: " + args.Message);

  }  

}

輸入

該範例採用 inlineSchema.xml 檔案做為輸入。

<root>
<!--Start of schema-->
<xs:schema xmlns:xs='http://www.w3.org/2001/XMLSchema'
            xmlns='xsdHeadCount'
            targetNamespace='xsdHeadCount'>
    <xs:element name='HeadCount'>
        <xs:complexType>
            <xs:sequence>
                <xs:element name='ID' type='xs:unsignedShort' maxOccurs='unbounded' />
            </xs:sequence>
            <xs:attribute name='division' type='xs:string' use='optional' default='QA'/>
        </xs:complexType>
    </xs:element>
</xs:schema>
<!--End of schema-->
<hc:HeadCount xmlns:hc='xsdHeadCount'>
    <ID>12365</ID>
    <ID>43295</ID>
    <division>Accounting</division>
</hc:HeadCount>
</root>

輸出

警告：   找不到相符的結構描述。未發生驗證。找不到項目 root 的結構描述資訊。

驗證錯誤：   項目 xsdHeadCount:HeadCount 含有無效的項目子系 division。預期的是 'ID'。

請參閱

概念

使用 XmlReader 讀取 XML

其他資源

使用 XmlReader 驗證 XML 資料