Transform a string into array using javascript

Question

I have a string like this:

string = "locations[0][street]=street&locations[0][street_no]=
 34&locations[1][street]=AnotherStreet&locations[1][street_no]=43";

What must I do with this string so i can play with locations[][] as I wish?

• Felix Kling: Where do you get the string from? It may be easier to create a proper JS object from the beginning.
• user447356: Looks like you'll have to use split using & as delimeter then use eval to evaluate each part. Can't you have more "proper" data source though?
• Leth: This is how i get my data and i can't do anything to change that unfortunately. Need to parse this as it is and right now i just can't thing at a way.

Answer 1

You could write a parser:

var myStr = "locations[0][street]=street&locations[0][street_no]=34&locations[1][street]=AnotherStreet&locations[1][street_no]=43";
function parseArray(str) {
 var arr = new Array();
 var tmp = myStr.split('&');
 var lastIdx;
 for (var i = 0; i < tmp.length; i++) {
 var parts = tmp[i].split('=');
 var m = parts[0].match(/\[[\w]+\]/g);
 var idx = m[0].substring(1, m[0].length - 1);
 var key = m[1].substring(1, m[1].length - 1);
 if (lastIdx != idx) {
 lastIdx = idx;
 arr.push({});
 }
 arr[idx * 1][key] = parts[1];
 }
 return arr;
}
var myArr = parseArray(myStr);

• Joe: +1 nice solution, although I think you meant push and not add
• Brian: @Joey - push is the instance method, which also would work. Array.add(instance, value) is adds a new index to an array.
• Leth: it throws this: Uncaught TypeError: Object function Array() { [native code] } has no method 'add', tried push, same error
• Joe: I'm just not sure you're getting much browser coverage with that, but either way.
• Brian: @Joey - touche! Gomoi got precisely what you were talking about... will update w/ push, not .add..

Answer 2

As Shadow wizard said, using split and eval seems to be the solution. You need to initialize locations first, if you want to avoid an error.

stringArray=string.split("&");
for (var i=0;i<stringArray.length;i++){
 eval(stringArray[i]);
}

However, you might need to pay attention to what street and street_no are. As is, it will produce an error because street is not defined.

Edit: and you'll need to fully initialize locations with as many item as you'll have to avoid an error.

• James Montagne: Be very careful using eval like this with a string coming from an external source. Unless the source is 100% trusted this is very dangerous.
• Py.: Yeah, i know this is some dangerous stuff, I try to avoid using it unless it's the only way (or if it's easier than the rest by far). Using regexp like Brian did seems a safer (and cleaner) way but a longer one.