Question

I have a string with one or more placeholders in the following format: $([name])

The [name] can be any word (containing alfanumeric chars) and is case sensitive.

 Example1: 'The $(Quick) Brown fox jumps over the lazy dog'
 Example2: '$(the) $(Quick) Brown fox jumps over $(the) lazy dog'
 Example3: '$(the) $(Quick) Brown $(fox) jumps over $(the) lazy $(dog)'

What is the best way in javascript to retrieve all place holders so that we have following result:

 Example1: ['Quick']
 Example2: ['the', 'Quick', 'the']
 Example3: ['the', 'Quick', 'fox', 'the', 'dog']

I also need to retrieve a unique list of placeholders, thus:

 Example1: ['Quick']
 Example2: ['the', 'Quick']
 Example3: ['the', 'Quick', 'fox', 'dog']

Thank you.

Answer 1

As other answers have mentioned, your best approach is to use regular expression with the JavaScript string.match() function. My regular expression isn’t the best it could be [whose is], but this should do the trick:

jsFiddle Demo

function getPlaceholders(str)
{
    var regex = /\$\((\w+)\)/g;
    var result = [];

    while (match = regex.exec(str))
    {
        result.push(match[1]);    
    }

    return result;
}

Thanks freakish
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