Parsing optional blocks with RegEx

I have to parse data contaning blocks that are not always present. Here's example

I want to catch each (aaa, bbb and ccc) blocks in corresponding variables. The problem is that some blocks can be omitted.

I tried this regex:

"( s)\s*" & _

"( :<block id=""aaa"">\s*( <aaa>.*)\s*</block>) \s*" & _

"( :<block id=""bbb"">\s*( <bbb>.*)\s*</block>) \s*" & _

"( :<block id=""ccc"">\s*( <ccc>.*)\s*</block>) \s*"

But it doesn't work. The first (aaa) block consumes other blocks.

How to change that

Hydra20010
Thnks. That really helped.

P.S. I was parsing <div> - based html pages
ManishPPPP
what are you looking to get from the pattern Do you want the id values from <block id="aaa">, etc (that is, "aaa", "bbb", etc) or the data between the start and end <block> tags (that is, aaa data, bbb data, xxx data, etc)

Imran.
J.Douglas
Your capture groups are greedy. Use non-greedy capturing, replacing * by * for all three capture groups.
Iainr
I want to get:
<aaa>= aaa data
<bbb>= bbb data <block > xxx data </block>
<ccc>= ccc data
sbogollu

is 1 or 0 times; is 0 or 1 times. I suggest you read up on regular expressions. A document I always found very useful is perlre, although there are probably lots of other manuals and tutorials you could read more specific to .NET regexes.

I didn't notice that your input data contained a nested block. Dealing with those can be quite tricky when using regular expressions... Have a look at this topic to see how to deal with nested elements.
parsec
"( s)\s*" & _
"( :<block id=""aaa"">\s*( <aaa>.* )\s*</block>) \s*" & _
"( :<block id=""bbb"">\s*( <bbb>.* )\s*</block>) \s*" & _
"( :<block id=""ccc"">\s*( <ccc>.* )\s*</block>) \s*"

This helps but partially. It results in

<aaa>="aaa data"
<bbb>="bbb data <block > xxx data"
<ccc>=""

Is there any "greedy " which would mean 0 or 1 times, but 1 preferred
Parsing optional blocks with RegEx