C# Regex expression that will capture selection between multiple sets of characters

Question

I want to be able to capture everything between sets of ## . For example the strings:

• ##First## the dog ate, ##second## the dog ran => ['First', 'second']
• The dog ##ran## => ['ran']
• ##The## dog ran away from ##home## => ['The', 'home']

I tried (?<=##).+?(?=#) but it captures the first string.

I am using C#

Answer 1

Because of the look behind and look ahead you are going to capture the string in-between first and second in ##First## the dog ate, ##second## the dog ran

To correct that, you need to consume them:

(?:##)(?<text>.+?)(?:##)

Then when you match, you can use the group text to extract the part you want.

For example:

var str = "##First## the dog ate, ##second## the dog ran";
var reg = new Regex("(?:##)(?<text>.+?)(?:##)");

var result = reg.Matches(str).Cast<Match>().Select(m => m.Groups["text"].Value);

result will contain First and second