I have a string that should be parsed to JSON and than should be converted to a Float32Array. The string looks like this:
{"vertices":"[-1.0, -1.0, -1.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0]"}
The Array should be assigned to a variable, e.g.:
mesh.vertices = new Float32Array([-1.0, -1.0, -1.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0]);
How can I convert the string so that the array consists of float numbers? For security reasons, I don´t want to use eval().
You could use JSON.parse:
mesh.vertices = new Float32Array(JSON.parse(myString).vertices);
This is assuming you meant:
{"vertices":[-1.0, -1.0, -1.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0]}
If the JSON is actually as you said (which FWIW is a bit weird), it'd be:
mesh.vertices = new Float32Array(JSON.parse(JSON.parse(myString).vertices));
Use JSON.parse to parse JSON data securely. See https://developer.mozilla.org/En/Using_native_JSON
I still suggest you to use the native JSON parser (as others mentioned), but here is a very simple and limited implementation:
var stringToParse = "{vertices:[-1.0, -1.0, -1.0, -1.0, -1.0, 0.0, 1.0, -1.0, 0.0]}";
Object.prototype.simpleParse = function() {
if (!(this instanceof String)) throw "Type mismatch";
var re = /(\w+)[^:]+:\[([^\]]+)\]/g;
var keyvalues = re.exec(this.valueOf());
var key = keyvalues[1];
var values = keyvalues[2].split(",");
var arr = [];
for (val in values) {
var currentValue = (/-?\d+(.\d+)?/).exec(values[val])[0];
arr.push(currentValue);
}
arr.pop();
ret = {};
ret[key] = new Float32Array(arr);
return ret;
}
console.log(stringToParse.simpleParse());
Demo: http://jsfiddle.net/mKWGH/
