Question

我没有太多使用XML，我需要一些帮助。

我的.NET应用程序从W3C的公共验证服务器获取此XML响应：

<?xml version="1.0" encoding="UTF-8" ?> 
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">
    <env:Body>
        <m:markupvalidationresponse env:encodingStyle="http://www.w3.org/2003/05/soap-encoding" xmlns:m="http://www.w3.org/2005/10/markup-validator">
            <m:uri>upload://Form Submission</m:uri> 
            <m:checkedby>http://validator.w3.org/</m:checkedby> 
            <m:doctype>-//W3C//DTD XHTML 1.1//EN</m:doctype> 
            <m:charset>utf-8</m:charset> 
            <m:validity>true</m:validity> 
            <m:errors>
                <m:errorcount>0</m:errorcount> 
                <m:errorlist /> 
            </m:errors>
            <m:warnings>
                <m:warningcount>0</m:warningcount> 
                <m:warninglist /> 
            </m:warnings>
        </m:markupvalidationresponse>
    </env:Body>
</env:Envelope>

我想从中提取以下值：

Uri as String
Checkedby as String
Doctype as String
CharSet as String
有效性为布尔值
ErrorList as System.Collections.Generic.List（Of W3CError）
WarningList as System.Collections.Generic.List（Of W3CError）

该类型W3CError是我使用以下属性创建的一个小类：

Line as Integer
Col as Integer
消息为字符串
MessageId as String
字符串解释
Source as String

这是我到目前为止所做的事情。但是，这不起作用 ......

Dim ResponseReader As Xml.XmlTextReader = New Xml.XmlTextReader(ResponseStream)
Dim ResponseDocument As New Xml.XPath.XPathDocument(ResponseReader)
Dim ResponseNavigator As Xml.XPath.XPathNavigator = ResponseDocument.CreateNavigator()
Dim ResponseIterator As Xml.XPath.XPathNodeIterator

'uri
ResponseIterator = ResponseNavigator.Select("uri")
ResponseIterator.MoveNext()
_Uri = ResponseIterator.Current.Value

'checked by
ResponseIterator = ResponseNavigator.Select("checkedby")
ResponseIterator.MoveNext()
_Checkedby = ResponseIterator.Current.Value

...etc...

如何解决上面破坏的代码？或者：我是否会偏离轨道？什么是更好的方式？

Answer 1

你听说过XPath吗？

XmlDocument doc  = new XmlDocument()
doc.Load(xml)
// set the namspace manager, I don't remember exact syntax
....
XmlNode node = doc.SelectSingleNode("//m:checkedby", namespaceManagerThatDeclaresMNamespace);

您的代码可能无法正常工作，因为您忽略了xml中的命名空间

Answer 2

试试这个

'Import these Namespaces at the top of your file
Imports System.Linq
Imports System.Xml.Linq
Imports <xmlns:env="http://www.w3.org/2003/05/soap-envelope">
Imports <xmlns:m="http://www.w3.org/2005/10/markup-validator">

'in a procedure do this
Dim doc As XDocument = <?xml version="1.0" encoding="UTF-8" ?> 
<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">
    <env:Body>
        <m:markupvalidationresponse env:encodingStyle="http://www.w3.org/2003/05/soap-encoding" xmlns:m="http://www.w3.org/2005/10/markup-validator">
            <m:uri>upload://Form Submission</m:uri> 
            <m:checkedby>http://validator.w3.org/</m:checkedby> 
            <m:doctype>-//W3C//DTD XHTML 1.1//EN</m:doctype> 
            <m:charset>utf-8</m:charset> 
            <m:validity>true</m:validity> 
            <m:errors>
                <m:errorcount>0</m:errorcount> 
                <m:errorlist /> 
            </m:errors>
            <m:warnings>
                <m:warningcount>0</m:warningcount> 
                <m:warninglist /> 
            </m:warnings>
        </m:markupvalidationresponse>
    </env:Body>
</env:Envelope>

_Uri = doc.Root.<env:Body>.<m:markupvalidationresponse>.<m:uri>.Value
_Checkedby = doc.Root.<env:Body>.<m:markupvalidationresponse>.<m:checkedby>.Value
'note that the following code assumes you have a class named W3CError
_errorList = (From er in doc.Root...<m:errors> _
             Select New W3CError With {.Line = CInt(er.<m:line>.Value), .Col = CInt(er.<m:col>.Value), .Message = er.<m:message>.Value, .MessageId = er.<m:messageId>.Value, .Explanation = er.<m:explanation>.Value, .Source = er.<m:source>.Value}).ToList
'do the same for the _warningList as above
'now do what you want with it

Answer 3

还有linq2xml。它位于System.Xml.Linq中。它有一个新的XDocument类，比旧的System.Xml.XmlDocument类更容易使用。

如何使用Visual Basic从XML文件中提取数据？

3 个答案: