問題描述

我有一個 XML 文件，我正在使用 XmlSchemaInference 類在運行時推斷其 XSD 架構.

I have an XML file and I'm inferring its XSD schema in run-time, using the XmlSchemaInference class.

示例文件:

<products>
    <product id="1" name="t-shirt">
        <size name="medium"/>
        <size name="large"/>
        <price>
            <net>10</net>
            <gross>25</gross>
        </price>
    </product>
    <product id="2" name="computer mouse">  
        <price>
            <net>50</net>       
        </price>
    </product>
</products>

它確實有效 - 它很好地推斷了架構:

It does work - it infers the schema nicely:

<?xml version="1.0"?>
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="products">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" name="product">
          <xs:complexType>
            <xs:sequence>
              <xs:element minOccurs="0" maxOccurs="unbounded" name="size">
                <xs:complexType>
                  <xs:attribute name="name" type="xs:string" use="required" />
                </xs:complexType>
              </xs:element>
              <xs:element name="price">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="net" type="xs:unsignedByte" />
                    <xs:element minOccurs="0" name="gross" type="xs:unsignedByte" />
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
            <xs:attribute name="id" type="xs:unsignedByte" use="required" />
            <xs:attribute name="name" type="xs:string" use="required" />
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

問題是:

如何迭代(遞歸?)通過此架構中的所有元素?XmlSchemaSet 類如何存儲它們?我需要將它們呈現給用戶，以便他們可以進行一些映射.

How can I iterate (recursively?) through all the elements from this schema? How are they stored by the XmlSchemaSet class? I need to present them to the user so they can do some mapping.

我正在從 XmlSchemaSet.Schemas 屬性中檢索 XmlSchema，然后呢?XmlSchema.Elements 只包含一項(products)，我找不到任何方法來查找它的子元素是什么.

I am retrieving an XmlSchema from XmlSchemaSet.Schemas property, and then what? XmlSchema.Elements only contains one item (products), and I can't find any way to look up what its subelements are.

推薦答案

好的！沒有答案，也沒有太大的興趣——我自己想出來的.

Okay! No answer and not much interest - I figured it out on my own.

我使用了我在谷歌上搜索的這篇 MSDN 文章中的代碼:遍歷 XML 模式

I used code from this MSDN article I googled up: Traversing XML Schemas

我的遞歸解決方案就是以此為基礎的.

And I based my recursive solution on it.

void PrintSchema(string xmlFilePath)
{
    var schemaSet = new XmlSchemaInference().InferSchema(XmlReader.Create(xmlFilePath));
    foreach (XmlSchemaElement element in schemaSet
        .Schemas()
        .Cast<XmlSchema>()
        .SelectMany(s => s.Elements.Values.Cast<XmlSchemaElement>()))
    {
        Debug.WriteLine(element.Name + " (element)");
        IterateOverElement(element.Name, element);
    }
}

void IterateOverElement(string root, XmlSchemaElement element)
{
    var complexType = element.ElementSchemaType as XmlSchemaComplexType;
    if (complexType == null) 
    {
        return;
    }
    if (complexType.AttributeUses.Count > 0)
    {
        var enumerator = complexType.AttributeUses.GetEnumerator();
        while (enumerator.MoveNext())
        {
            var attribute = (XmlSchemaAttribute)enumerator.Value;
            Debug.WriteLine(root + "." + attribute.Name + " (attribute)");
        }
    }
    var sequence = complexType.ContentTypeParticle as XmlSchemaSequence;
    if (sequence == null) 
    {
        return;
    }
    foreach (XmlSchemaElement childElement in sequence.Items)
    {
        root += String.Concat(".", childElement.Name);
        Debug.WriteLine(root + " (element)");
        // recursion
        IterateOverElement(root, childElement);
    }
}

輸出為:

products (element)
products.product (element)
products.product.id (attribute)
products.product.name (attribute)
products.product.size (element)
products.product.size.name (attribute)
products.product.price (element)
products.product.price.net (element)
products.product.price.gross (element)

我讓你來判斷這個 API 的友好程度，特別是考慮到這些特定類的 MSDN 文檔是多么稀缺.感謝您提出任何意見或見解.

I leave to you to judge how friendly this API is, especially given how scarce is the MSDN documentation on these particular classes. Any comments or insights are appreciated.

這篇關于從 XML 文件推斷的 XmlSchema - 如何遍歷 XSD 中的所有元素?的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！