Regular expression to find href tags. - C# Discussion Boards

Regular expression to find href tags.

12-Sep-08 6:12

Implement IComparable on your object, and set Sorted = true.

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

xml + nillable

pbennington12-Sep-08 6:03

pbennington

12-Sep-08 6:03

Hi,
could anyone help me and tell me how i could change the following code so that the resulting xml would have nillable="true" on the field elements so that null values are represented with xsi:nil="true" in the xml?

SqlConnection MSSqlConn = new SqlConnection();

SqlCommand MSSCommand = new SqlCommand();

SqlDataAdapter MSdataAdapter = new SqlDataAdapter();

DataTable MyDT = new DataTable("TestQuery");

MSSqlConn.ConnectionString = str_con;

MSSCommand.Connection = MSSqlConn;

MSSCommand.CommandText = "select * from order_header where order_header.order_date = '09/13/2008'";

MSdataAdapter.SelectCommand = MSSCommand;

MSdataAdapter.Fill(MyDT);

MyDT.WriteXml("c:\\testquery.xml", XmlWriteMode.WriteSchema);

Pav197712-Sep-08 5:43

Pav1977

12-Sep-08 5:43

Hi there,

I'm new to C# and .NET and just wandering if there is anything clever that I could download (library, etc.) or maybe is part of the standard C# library that could help this:

In an import scenario (of tousands of articles) I have a column in the database that contains links. This is a very messy database (from a CMS) and some of the links are www.somelink.com (the good ones), etc. some are actualy with the html tag <a href="http://somelink.com">www.somelink.com</a>

I was wandering if there is a regular expression anywhere that would help me to filter out the Web link?

In the worst case scenario I'll have to write it myself - not a huge worry but would prefere to resuse of course.

Any help much appreciated.

Kind regards,

Pav

Re: Regular expression to find href tags.

M Harris12-Sep-08 6:19

M Harris

12-Sep-08 6:19

<a.+?href>]*>(?<text>.+?)

should about do it Smile | :)

I just wrote that for you, should get you three named match groups: "HREF", "Domain", "Text".

My test data was:
asd
asd
asd
asd
asd

all matched correctly.

--
Real programmers don't comment their code. It was hard to write, it should be hard to understand.

Re: Regular expression to find href tags.

Mohammad Dayyan12-Sep-08 11:04

Mohammad Dayyan

12-Sep-08 11:04

Try this :

<(a|A)[^>]*>[^<]*<\/(a|A)>

Further learning : http://www.regular-expressions.info/[^]

modified on Friday, September 12, 2008 5:10 PM

Re: Regular expression to find href tags.

Mike Hankey12-Sep-08 17:20

Mike Hankey

12-Sep-08 17:20

Try Expresso, its a very handy tool if your going to be doing regular expressions. It also contains a small library of reg. expressions for common problems.

Here[^]

Mike

Semper Fi
http://www.hq4thmarinescomm.com[^]
My Site

How would you write this in Linq?

Marc Clifton12-Sep-08 4:34

12-Sep-08 4:34

I admit to ignorance and some laziness. There.

Never having written a Linq expression, (or in this case, is it a simple lambda expression?) I'm humbly asking for an example, as I'd like to start learning this feature.

Here's the code. It should be obvious what I'm trying to do.

// ignore lines that have chars other than digits and whitespace
bool bad=false;

foreach (char c in failure.ToCharArray())
{
  if (!Char.IsDigit(c) && !Char.IsWhiteSpace(c))
  {
    bad = true;
    break;
  }
}

Thanks!

Marc

led mike12-Sep-08 4:39

led mike

12-Sep-08 4:39

Well I don't know how to write the LINQ but I would have posted the question in the LINQ forum. What a Nub Poke tongue | ;-P

led mike

Marc Clifton12-Sep-08 4:40

12-Sep-08 4:40

led mike wrote:
Well I don't know how to write the LINQ but I would have posted the question in the LINQ forum. What a Nub

We have a Linq forum? Oh! You're right. What a Nub I am!

Marc

Re: How would you write this in Linq? [modified]

leppie12-Sep-08 4:54

12-Sep-08 4:54

You cant do that in Linq (because of the break statement) Smile | :)

But you can do something with same effect.

<font color="Blue">string</font> failure <font color="DarkBlue">=</font> <font color="Maroon">"fob"</font><font color="DarkBlue">;</font>

<font color="Blue">bool</font> bad <font color="DarkBlue">=</font> <font color="DarkBlue">(</font><font color="Blue">from</font> c <font color="Blue">in</font> failure
            <font color="Blue">where</font> <font color="DarkBlue">!</font><font color="DarkBlue">(</font><font color="Blue">char</font><font color="DarkBlue">.</font>IsWhiteSpace<font color="DarkBlue">(</font>c<font color="DarkBlue">)</font> <font color="DarkBlue">||</font> <font color="Blue">char</font><font color="DarkBlue">.</font>IsDigit<font color="DarkBlue">(</font>c<font color="DarkBlue">)</font><font color="DarkBlue">)</font>
            <font color="Blue">select</font> c<font color="DarkBlue">)</font><font color="DarkBlue">.</font>Count<font color="DarkBlue">(</font><font color="DarkBlue">)</font> <font color="DarkBlue">></font> <font color="Red">0</font><font color="DarkBlue">;</font>

[update] fixed the query Roll eyes | :rolleyes:

[update]

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

modified on Friday, September 12, 2008 11:44 AM

Marc Clifton12-Sep-08 4:58

12-Sep-08 4:58

I was wondering about that, because of the break statement.

So. That's, umm, disappointing. I certainly don't want to process a million character string if the first char in the string is 'A'.

Marc

leppie12-Sep-08 4:58

Re: How would you write this in Linq? [modified]

12-Sep-08 4:58

See my reply to myself Smile | :)

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

leppie12-Sep-08 5:02

12-Sep-08 5:02

Actually, you could still use the Linq functions, but not a query pre se. The ~~Contains~~ Any function takes a predicate.

bad = failure.Any(c => !(char.IsWhiteSpace(c) || char.IsDigit(c)));

[update] fixed the missing ! part Roll eyes | :rolleyes:

[update]

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

modified on Friday, September 12, 2008 11:41 AM

Marc Clifton12-Sep-08 5:28

12-Sep-08 5:28

leppie wrote:
Any function takes a predicate.

Coolness! That's what I was looking for.

Thank you!

Marc

Marc Clifton12-Sep-08 5:35

12-Sep-08 5:35

leppie wrote:
bad = failure.Any(c => char.IsWhiteSpace(c) || char.IsDigit(c));

Except, wouldn't the logic be:

bool bad = failure.Any(c => (!char.IsWhiteSpace(c) && !char.IsDigit(c)));

Marc

leppie12-Sep-08 5:50

Re: How would you write this in Linq? [modified]

12-Sep-08 5:50

Yeah

I forgot the ! part in front of the condition. It is fixed now.

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

Eslam Afifi12-Sep-08 6:12

Eslam Afifi

12-Sep-08 6:12

From your original post I assume you want to do some sort of processing on the valid lines so i think you can use the Where method.

foreach (var line in allLines.Where(s => s.Any(c => !(char.IsWhiteSpace(c) || char.IsDigit(c)))))
//I think using 2 operator instead of 3 will execute faster if the compiler doesn't optimize that
{ }

You might find the Select method useful, something like

allLines.Where(s => s.Any(c => !(char.IsWhiteSpace(c) || char.IsDigit(c)))).Select(s => s.Length);

Eslam Afifi

modified on Friday, September 12, 2008 1:04 PM

leppie12-Sep-08 5:08

12-Sep-08 5:08

Marc Clifton wrote:
So. That's, umm, disappointing. I certainly don't want to process a million character string if the first char in the string is 'A'.

Technically it would be possible for the Count function to break early, if it could infer the resulting comparison, thus resulting in an Any function as per the other example.

[update] I did a test, it does not appear to do it for a string enumerable, I do however believe that SQL will be optimized if running the same query over a database source. [update]

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

led mike12-Sep-08 5:25

led mike

12-Sep-08 5:25

leppie wrote:
I do however believe that SQL will be optimized if running the same query over a database source.

Huh? I'm LINQless so I have no idea what that means.

led mike

leppie12-Sep-08 5:38