Replacing A Node Using HtmlAgilityPack Throwing Strange Error

Question

I have a webpage that displays a table the user can edit. After the edits are made I want to save the table as a .html file that I can convert to an image later. I am doing this by overriding the render method. However, I want to remove two buttons and a DropDownList from the final version so that I just get the table by itself. Here is the code I am currently trying:

protected override void Render(HtmlTextWriter writer)
{
    using (HtmlTextWriter htmlwriter = new HtmlTextWriter(new StringWriter()))
    {
        base.Render(htmlwriter);
        string renderedContent = htmlwriter.InnerWriter.ToString();
        string output = renderedContent.Replace(@"<input type=""submit"" name=""viewReport"" value=""View Report"" id=""viewReport"" />", "");
        output = output.Replace(@"<input type=""submit"" name=""redoEdits"" value=""Redo Edits"" id=""redoEdits"" />", "");

        var doc = new HtmlDocument();
        doc.LoadHtml(output);

        var query = doc.DocumentNode.Descendants("select");
        foreach (var item in query.ToList())
        {
            var newNodeStr = "<div></div>";
            var newNode = HtmlNode.CreateNode(newNodeStr);
            item.ParentNode.ReplaceChild(newNode, item);
        }

        File.WriteAllText(currDir + "\\outputFile.html", output);

        writer.Write(renderedContent);
    }
}

Where I have adapted this solution found in another SO post about replacing nodes with HtmlAgilityPack:

var htmlStr = "<b>bold_one</b><strong>strong</strong><b>bold_two</b>";
var doc = new HtmlDocument();
doc.LoadHtml(htmlStr);

var query = doc.DocumentNode.Descendants("b");
foreach (var item in query.ToList())
{
    var newNodeStr = "<foo>bar</foo>";
    var newNode = HtmlNode.CreateNode(newNodeStr);
    item.ParentNode.ReplaceChild(newNode, item);
}

and here is the rendered HTML I am trying to alter:

<select name="Archives" onchange="javascript:setTimeout(&#39;__doPostBack(\&#39;Archives\&#39;,\&#39;\&#39;)&#39;, 0)" id="Archives" style="width:200px;">
    <option selected="selected" value="Dashboard_Jul-2012">Dashboard_Jul-2012</option>
    <option value="Dashboard_Jun-2012">Dashboard_Jun-2012</option>
</select>

The two calls to Replace are working as expected and removing the buttons. However this line:

var query = doc.DocumentNode.Descendants("select");

is throwing this error:

Method not found: 'Int32 System.Environment.get_CurrentManagedThreadId()'.

Any advice is appreciated.

Regards.

score 2 · Accepted Answer · answered Aug 21 '12 at 07:38

2

Seems like you are using the .Net 4.5 Version of the Agility Pack in a project targeting .Net or lower, you just have to either change the reference of the Dll to the one compiled for your Framework version or change your project to .Net 4.5 (if you're using VS 2012 that is).

answered Aug 21 '12 at 07:38

shriek

5,157
2
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42

Many thanks. That took care of the error. But now the node isn't being replaced by the empty div. Do you have any suggestions? – Kevin Aug 21 '12 at 12:34
Okay, found it. I needed `doc.Save()`. Thanks for your help – Kevin Aug 21 '12 at 16:03

Replacing A Node Using HtmlAgilityPack Throwing Strange Error

1 Answers1