Read a String like a StreamReader

Question

First of all: Sorry for my bad English!

I know the title isn't the best English, but I don't really know how to format this question...
What I'm trying to do is reading an HTML source line by line so when it sees a given word (like http://) it copies the entire sentence so I can strip the rest an only keep the URL.

This is what I've tried:

using (var source = new StreamReader(TempFile))
{
    string line;
    while ((line = source.ReadLine()) != null)
    {
        if (line.Contains("http://"))
        {
            Console.WriteLine(line);
        }
    }
}

This works perfectly if I want to read it from an external file but it doesn't work when I want to read an string or stringbuilder, how do you read those line by line?

score 7 · Accepted Answer · answered Jul 10 '12 at 22:27

7

You can use new StringReader(theString) to do that with a string, but I question your overall strategy. That would be better done with a tool like HTML Agility Pack.

For example, here is HTML Agility Pack extracting all hyperlinks:

HtmlDocument doc = new HtmlDocument();
doc.LoadHtml(theString);
foreach(HtmlNode link in doc.DocumentElement.SelectNodes("//a[@href]")
{
   HtmlAttribute att = link["href"];
   Console.WriteLine(att.Value);
}

answered Jul 10 '12 at 22:27

Marc Gravell

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I agree. Also make sure to use ScrapySharp as well with HtmlAgilityPack. It let's you use familiar jQuery syntax to select elements. Literally doubles your productivity. http://www.romcyber.com/post/2012/01/27/ScrapySharp-in-english-%29.aspx – Only Bolivian Here Jul 10 '12 at 22:30
But that's another dependency... Not saying it's necessarily bad, just a thing to consider. – vines Jul 10 '12 at 22:35
1

@vines: A trivial issue. The library is very small. – Only Bolivian Here Jul 10 '12 at 22:36
1

@vines compared to parsing html **properly**, it is a trivial thing – Marc Gravell Jul 10 '12 at 22:36
@MarcGravell I don't think this code is going to work, mainly because the link is somewhere in a javascript :(. – Yuki Kutsuya Jul 10 '12 at 23:08

score 0 · Answer 2 · answered Jul 10 '12 at 22:27

Well a string is just a string, it doesn't have any lines.

You can use something like String.Split to separate on the \r symbol.

MSDN: String.Split()

string words = "This is a list of words, with: a bit of punctuation" +
                       "\rand a newline character.";

string [] split = words.Split(new Char [] {'\r' });

foreach (string s in split) {
    if (s.Trim() != "")       
        Console.WriteLine(s);
}

score 0 · Answer 3 · edited May 23 '17 at 10:34

0

Firstly, you can use a StringReader.

Another option is to create a MemoryStream from the string via converting the string to a byte array first, as described in https://stackoverflow.com/a/10380166/396583

edited May 23 '17 at 10:34

Community

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answered Jul 10 '12 at 22:32

vines

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score 0 · Answer 4 · answered Jul 10 '12 at 22:35

0

I think you can tokenize the input and check each entry for the required content.

 string[] info = myStringBuilder.toString().split[' '];
 foreach(var item in info) {
 if(item.Contains('http://') {
    //work with it
    }
 }

answered Jul 10 '12 at 22:35

vishakvkt

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score 0 · Answer 5 · answered Jul 10 '12 at 22:36

0

You can use a memory stream to read from.

answered Jul 10 '12 at 22:36

SargeATM

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Read a String like a StreamReader

5 Answers5