模式验证 XML

Question

我有一个 XSD 文件和一个 XML 文件，如何检查 XML 是否像 XSD 文件一样在正确的架构中？

我知道XmlDocument 类中有一个验证函数，但它需要一个事件处理程序 我只需要对或错。

附：我在 Visual Studio 2010 中工作。

Answer 1

您可以使用 XmlReaderSettings 类和 Create 方法创建一个验证 XmlReader 实例。

private bool ValidateXml(string xmlFilePath, string schemaFilePath, string schemaNamespace, Type rootType)
{
    XmlSerializer serializer = new XmlSerializer(rootType);

    using (var fs = new StreamReader(xmlFilePath, Encoding.GetEncoding("iso-8859-1")))
    {
        object deserializedObject;
        var xmlReaderSettings = new XmlReaderSettings();
        if (File.Exists(schemaFilePath))
        {
            //select schema for validation  
            xmlReaderSettings.Schemas.Add(schemaNamespace, schemaPath); 
            xmlReaderSettings.ValidationType = ValidationType.Schema;
            try
            {
            using (var xmlReader = XmlReader.Create(fs, xmlReaderSettings))
            {                
                if (serializer.CanDeserialize(xmlReader))
                {
                    return true;
                    //deserializedObject = serializer.Deserialize(xmlReader);
                }
                else
                {
                    return false;
                }
            }
            }
            catch(Exception ex)
            { return false; }
        }
    }
}

如果架构无效或无法反序列化xml，上述代码将抛出异常。 rootType 是等效类层次结构中根元素的类型。

---

示例： 架构位于：XML Schema Tutorial。将文件另存为D:\SampleSchema.xsd。

运行xsd.exe：

1. 打开“开始菜单 > 所有程序 > Microsoft Visual Studio 2010 > Visual Studio 工具 > Visual Studio 2010 命令提示符”
2. 在命令提示符下，键入：xsd.exe /c /out:D:\ "D:\SampleSchema.xsd"
3. xsd选项：/out选项指定输出目录，/c指定生成类的工具
4. 输出类层次结构存在于D:\SampleSchema.cs
5. 生成的类层次结构看起来像这样，

//------------------------------------------------------------------------------
// 
//     This code was generated by a tool.
//     Runtime Version:2.0.50727.4952
//
//     Changes to this file may cause incorrect behavior and will be lost if
//     the code is regenerated.
// 
//------------------------------------------------------------------------------

using System.Xml.Serialization;

// 
// This source code was auto-generated by xsd, Version=2.0.50727.3038.
// 


/// 
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType=true)]
[System.Xml.Serialization.XmlRootAttribute(Namespace="", IsNullable=false)]
public partial class note {

    private string toField;

    private string fromField;

    private string headingField;

    private string bodyField;

    /// 
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public string to {
        get {
            return this.toField;
        }
        set {
            this.toField = value;
        }
    }

    /// 
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public string from {
        get {
            return this.fromField;
        }
        set {
            this.fromField = value;
        }
    }

    /// 
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public string heading {
        get {
            return this.headingField;
        }
        set {
            this.headingField = value;
        }
    }

    /// 
    [System.Xml.Serialization.XmlElementAttribute(Form=System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public string body {
        get {
            return this.bodyField;
        }
        set {
            this.bodyField = value;
        }
    }
}

---

将该类添加到 Visual Studio 项目中。
对于上面的 xsd 示例，根类是 note。
调用方法，

bool isXmlValid = ValidateXml(@"D:\Sample.xml", 
                              @"D:\SampleSchema.xsd", 
                              @"http://www.w3.org/2001/XMLSchema", 
                              typeof(note));

更多信息：

• Validation Against XML Schema (XSD) with the XmlValidatingReader
• XML Schema Definition Tool (Xsd.exe)

Answer 2

你可以这样做。

public class XmlValidator
{
    private bool _isValid = true;

    public bool Validate(string xml)
    {
        _isValid = true;

        // Set the validation settings as needed.
        var settings = new XmlReaderSettings { ValidationType = ValidationType.Schema };
        settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessInlineSchema;
        settings.ValidationFlags |= XmlSchemaValidationFlags.ProcessSchemaLocation;
        settings.ValidationFlags |= XmlSchemaValidationFlags.ReportValidationWarnings;
        settings.ValidationEventHandler += ValidationCallBack;

        var reader = XmlReader.Create(new StringReader(xml), settings);

        while(reader.Read())
        {
            // process the content if needed
        }

        return _isValid;
    }

    private void ValidationCallBack(object sender, ValidationEventArgs e)
    {
        // check for severity as needed
        if(e.Severity == XmlSeverityType.Error)
        {
            _isValid = false;
        }
    }
}

class Program
{

    static void Main(string[] args)
    {
        var validator = new XmlValidator();

        var result =
            validator.Validate(@"<?xml version=""1.0""?>
                 <Product ProductID=""1"" xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xsi:noNamespaceSchemaLocation=""schema.xsd"">
                     <ProductName>Chairs</ProductName>
                 </Product>");

}

架构。

<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
   <xsd:element name="Product">
      <xsd:complexType>
         <xsd:sequence>
            <xsd:element name="ProductName" type="xsd:string"/>
         </xsd:sequence>
         <xsd:attribute name="ProductID" use="required" type="xsd:int"/>
      </xsd:complexType>
   </xsd:element>
</xsd:schema>

Answer 3

有一个非常简单的方法：

private void ValidationCallBack(object sender, ValidationEventArgs e)
{  
    throw new Exception();
}

public bool validate(string sxml)
{
    try
    {
        XmlDocument xmld=new XmlDocument ();
        xmld.LoadXml(sxml);
        xmld.Schemas.Add(null,@"c:\the file location");
        xmld.validate(ValidationCallBack);
        return true;
    }
    catch
    {
        return false;
    }
}

P.S : 我不是在 VS 中写的，所以可能会有不区分大小写的单词，但这段代码有效！