Hiddentrak

If you’re programming experience is primarily based in the world of Flash, you may not have had much exposure to regular expressions. With it’s inclusion in AS3, we now have some very powerful, and helpful tools available to us. I just wanted to post a quick snippet of how you might use regular expressions in your development.

[as]//regex that finds and replaces tokens in a string
function replaceTokens(str:String,paramObj:Object) : String{
//token structure ${tokenName}
var myRegEx:RegExp = /\$\{([a-zA-Z0-9]+)\}/g;
return str.replace(myRegEx,function(){return paramObj[arguments[1]]});
}[/as]

The regular expression we are concerned with is:
[as]var myRegEx:RegExp = /\$\{([a-zA-Z0-9]+)\}/g;[/as]

When this pattern is run against some input it matches the dollar sign, then an open brace, any letter or number and then a closing brace. Like so: ${exampleToken} The function we put together takes those matches and replaces the value with a match in the paramObj.