For getting JSON file

get_json.js

// for gitting JSON file

// \brief get JSON file
// \param(file_name) target JSON file name
// \ret JSON file
function get_json(file_name) {
	var requester = create_http_request();
	requester.open("GET", file_name, false);
	
	requester.send(null);
	var json_text = requester.responseText;
	var data = json_parser(json_text);
	return data;
}


// \brief create requester for getting files
// \todo support old browser (ex: IE6, IE5)
function create_http_request() {
	var requester = null;
	
	// for modern browser
	if(window.XMLHttpRequest) {
		requester = new XMLHttpRequest();
	}
	
	return requester;
}


// \brief return true when posible JSON object
// refer to "http://stackoverflow.com/questions/1787020/json-object-in-ie6-how"
function enable_json() {
	if(!this.JSON) {
		return false;
	}
	
	return true;
}


// \brief translate JSON into Javascript object
// \param(json_data) JSON
// \ret 
function json_parser(json_data) {
	var data = new String();
	
	if(enable_json()) {
		data = JSON.parse(json_data);
	}
	else {
		// security warning because use eval function
		data = eval("(" + json_data + ")");
	}
	
	return data;
}