C#检查xml where属性中是否存在元素
我需要检查我的XML文档是否存在同名的某个元素C#检查xml where属性中是否存在元素,c#,sql,xml,function,parsing,C#,Sql,Xml,Function,Parsing,我需要检查我的XML文档是否存在同名的某个元素 channel-category 其中元素属性等于某个id channel id="X" 我有以下函数,但它总是返回false,即使它确实存在 static bool exists(string channelname) { string path; string xmlfile = "\\xmlfile.xml"; path = Environment.CurrentDirectory
channel-category
其中元素属性等于某个id
channel id="X"
我有以下函数,但它总是返回false,即使它确实存在
static bool exists(string channelname)
{
string path;
string xmlfile = "\\xmlfile.xml";
path = Environment.CurrentDirectory + xmlfile;
XDocument xmlDoc = XDocument.Load(path);
bool doesexists = (from data in xmlDoc.Element("tv").Elements("channel").Elements("channel-category")
where (string)data.Attribute("id") == channelname
select data).Any();
return doesexists;
}
下面是我的xml的一个示例
<tv info="blahblah">
<channel id="Channelname1">
<display-name lang="en">Channelname1</display-name>
<icon src="somelogo.png" />
<url>http://somelink.com</url>
<channel-category>SomeValue</channel-category>
</channel>
<channel id="Channelname2">
<display-name lang="en">Channelname2</display-name>
<icon src="somelogo.png" />
<url>http://somelink.com</url>
</channel>
</tv>
频道名称1
http://somelink.com
一些价值
频道名称2
http://somelink.com
现在,函数应该为id Channelname1返回true,为id Channelname2返回false,但这两个函数都返回false,我不知道为什么。有什么想法吗?您必须使用XDocument和Linq2Xml吗? 使用XmlDocument类和XPath怎么样
static bool exists(string channelname)
{
string path;
string xmlfile = "\\xmlfile.xml";
path = Environment.CurrentDirectory + xmlfile;
XmlDocument doc = XmlDocument.Load(path);
return doc.SelectSingleNode("//tv/channel[@id=" + channelname + "]/channel-category") != null;
}
您必须使用XDocument和Linq2Xml吗? 使用XmlDocument类和XPath怎么样
static bool exists(string channelname)
{
string path;
string xmlfile = "\\xmlfile.xml";
path = Environment.CurrentDirectory + xmlfile;
XmlDocument doc = XmlDocument.Load(path);
return doc.SelectSingleNode("//tv/channel[@id=" + channelname + "]/channel-category") != null;
}
我同意HaukurHaf,或者您也可以编写简单的
Linq
语句,如下所示
static bool exists(string channelname)
{
string path;
string xmlfile = "\\xmlfile.xml";
path = Environment.CurrentDirectory + xmlfile;
XmlDocument doc = XmlDocument.Load(path);
return (doc.Descendants("channel").Any(x => (string) x.Attribute("id") == channelname && x.Element("channel-category") != null);
}
尝试这项工作我同意HaukurHaf,或者您也可以编写简单的
Linq
语句,如下所示
static bool exists(string channelname)
{
string path;
string xmlfile = "\\xmlfile.xml";
path = Environment.CurrentDirectory + xmlfile;
XmlDocument doc = XmlDocument.Load(path);
return (doc.Descendants("channel").Any(x => (string) x.Attribute("id") == channelname && x.Element("channel-category") != null);
}
试试这个工作谢谢回复!不幸的是,它仍然返回false
if(exists(allchannels)){Console.WriteLine(“已存在!”);}else
函数返回false并点击elsestring.Concat返回的“//tv/channel[@id=Channelname1]/channel类别”string System.Xml.XmlNode.SelectSingleNode返回空System.Xml.XmlNode channelname“Channelname1”字符串
感谢您的回复!不幸的是,它仍然返回falseif(exists(allchannels)){Console.WriteLine(“已存在!”);}else
函数返回false并点击elsestring.Concat返回的“//tv/channel[@id=Channelname1]/channel类别”string System.Xml.XmlNode.SelectSingleNode返回空System.Xml.XmlNode channelname“Channelname1”字符串