HtmlAgilityPack在Windows商店应用 [英] HtmlAgilityPack in windows store app
问题描述
所以我不得不在一个控制台应用程序工作的一些测试代码，那我动过到Windows商店应用。现在的问题是，我刚复制，我在我的控制台应用程序，现在它不工作的HtmlAgilityPack代码。我确实有HtmlAgilityPack作为参考...
现在的HtmlAgilityPack的一些不工作。什么是不工作的结果
使用（VAR的客户=新的WebClient（））刚刚经历错误的类型或命名空间名称的WebClient'找不到（是否缺少using指令或程序集引用？）
和下一部分不工作为
在doc.DocumentNode.SelectNodes（的foreach（HtmlNode链接//一个[ @href]））的一部分的selectNodes，出现错误'HtmlAgilityPack.HtmlNode'不包含'的SelectNodes的定义，并没有扩展方法'的SelectNodes接受型HtmlAgilityPack.HtmlNode'的第一个参数可能是（是否缺少using指令或程序集引用）
现在ñ知道的Html敏捷性包依赖于.NET的XPath实现。这WinRT的不支持XPATH。现在的问题是，我将如何完成下同的东西，会在Windows商店应用运行？
下面的代码做了以下几点。从下载 http://www.dubstep.net/track/5436 中的HTML页面，通过循环它寻找HREF，一旦它找到一个＃。这需要在href它上面和并且将其作为一个URI来启动。
我已经验证，下面的代码不会在控制台应用程序的工作。
使用（VAR的客户=新的WebClient（））
{
//下载HTML
字符串的html = client.DownloadString（http://www.dubstep.net/track/5436）;
//现在把它交给HTML敏捷性包：
的HTMLDocument DOC =新的HTMLDocument（）;
doc.LoadHtml（HTML）;
INT I = 0;
//现在你可以查询DOM。例如，你可以提取
//从所有锚的所有HREF属性：
名单，LT;字符串>名单=新名单，LT;串>（）;
的foreach（在doc.DocumentNode.SelectNodes（HtmlNode链接//一个[@href]））
{
HtmlAttribute HREF = link.Attributes [HREF];
如果（HREF！= NULL）
{
list.Add（href.Value）;
I ++;
如果（href.Value ==＃）
{
INT T = I - 2;
乌里试验=新的URI（列表[T]）;
开始（试验）;
}
}
}
}
公共静态无效的开始（URI T）
{
乌里remoteUri =新的URI （http://soundcloud.com/dubstep/spag-heddy-the-master-vip/download）;
串FILENAME1 =T，myStringWebResource = NULL;
//创建一个新的WebClient实例。
使用（Web客户端myWebClient =新的WebClient（））
{
myWebClient.DownloadFileCompleted + = DownloadCompleted;
myWebClient.DownloadProgressChanged + = myWebClient_DownloadProgressChanged;
myWebClient.DownloadFileAsync（T，file.mp3）;
}
}
您可以尝试更换 Web客户端与 HtmlWeb 和使用HtmlAgilityPack的LINQ API，而不是XPath中，使其工作在Windows应用商店中的应用程序
//使用HAP的htmlWeb，而不是Web客户端
变种htmlweb =新htmlWeb（）;从网页URL
的HTMLDocument DOC = htmlweb.Load（http://www.dubstep.net/track/5436）
//负荷的HTMLDocument;
INT I = 0;
名单，LT;字符串>名单=新名单，LT;串>（）;
//使用LINQ API来选择所有`< A>``有属性href`
VAR链接= doc.DocumentNode
.DescendantsAndSelf（A）
。凡（O => o.GetAttributeValue（的href，NULL）！= NULL）;
的foreach（在链接HtmlNode链接）
{
HtmlAttribute HREF = link.Attributes [HREF];
如果（HREF！= NULL）
{
list.Add（href.Value）;
I ++;
如果（href.Value ==＃）
{
INT T = I - 2;
乌里试验=新的URI（列表[T]）;
开始（试验）;
}
}
}
So I had some working test code in a console app, that I am moving over to a windows store app. NoW the problem is, ive just copied over the HtmlAgilityPack code that I had in my console app and now it doesnt work. I do have HtmlAgilityPack as a reference...
Now some of the HtmlAgilityPack does work. what is not working is
"using (var client = new WebClient())" just through the error "The type or namespace name 'WebClient' could not be found (are you missing a using directive or an assembly reference?)"
and the next part that does not work is " foreach (HtmlNode link in doc.DocumentNode.SelectNodes("//a[@href]"))" at the selectnodes part, with the error "'HtmlAgilityPack.HtmlNode' does not contain a definition for 'SelectNodes' and no extension method 'SelectNodes' accepting a first argument of type 'HtmlAgilityPack.HtmlNode' could be found (are you missing a using directive or an assembly reference)"
Now N know that Html Agility Pack relies on .NET for the XPATH implementation. And that WinRT doesn't support XPATH. Now my question is, how would I accomplish the same below with something that will run in a windows store app?
The code below does the the following. Downloads the html page from http://www.dubstep.net/track/5436, loops through it looking for href, once it finds a #. It takes the href above it and and sends it as a uri to start.
i have verified that the code below does work in a console application.
using (var client = new WebClient())
{
// Download the HTML
string html = client.DownloadString("http://www.dubstep.net/track/5436");
// Now feed it to HTML Agility Pack:
HtmlDocument doc = new HtmlDocument();
doc.LoadHtml(html);
int i = 0;
// Now you could query the DOM. For example you could extract
// all href attributes from all anchors:
List<string> list = new List<string>();
foreach (HtmlNode link in doc.DocumentNode.SelectNodes("//a[@href]"))
{
HtmlAttribute href = link.Attributes["href"];
if (href != null)
{
list.Add(href.Value);
i++;
if (href.Value == "#")
{
int t = i - 2;
Uri test = new Uri(list[t]);
start(test);
}
}
}
}
public static void start(Uri t)
{
Uri remoteUri = new Uri("http://soundcloud.com/dubstep/spag-heddy-the-master-vip/download");
string fileName1 = "t", myStringWebResource = null;
// Create a new WebClient instance.
using (WebClient myWebClient = new WebClient())
{
myWebClient.DownloadFileCompleted += DownloadCompleted;
myWebClient.DownloadProgressChanged += myWebClient_DownloadProgressChanged;
myWebClient.DownloadFileAsync(t, "file.mp3");
}
}
You can try to replace WebClient with HtmlWeb and use HtmlAgilityPack's LINQ API instead of XPath, to make it works in Windows Store apps :
//use HAP's HtmlWeb instead of WebClient
var htmlweb = new HtmlWeb();
// load HtmlDocument from web URL
HtmlDocument doc = htmlweb.Load("http://www.dubstep.net/track/5436");
int i = 0;
List<string> list = new List<string>();
//use LINQ API to select all `<a>` having `href` attribute
var links = doc.DocumentNode
.DescendantsAndSelf("a")
.Where(o => o.GetAttributeValue("href", null) != null);
foreach (HtmlNode link in links)
{
HtmlAttribute href = link.Attributes["href"];
if (href != null)
{
list.Add(href.Value);
i++;
if (href.Value == "#")
{
int t = i - 2;
Uri test = new Uri(list[t]);
start(test);
}
}
}
这篇关于HtmlAgilityPack在Windows商店应用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
