node-emv/util.js

The EMV parser library

exports.checkBin = function(n){
	return/^[01]{1,64}$/.test(n);
}

exports.checkDec = function(n){
	return/^[0-9]{1,64}$/.test(n);
}

exports.checkHex = function(n){
	return/^[0-9A-Fa-f]{1,64}$/.test(n);
}

exports.pad = function(s,z){
	s = "" + s;
	return s.length < z ? this.pad("0" + s, z) : s;
}

exports.unpad = function(s){
	s = "" + s;
	return s.replace(/^0+/,'');
}

exports.Dec2Bin = function(n){
	if(!this.checkDec(n) || n < 0)
		return 0;
	return n.toString(2);
}
exports.Dec2Hex = function (n){
	if(!this.checkDec(n) || n < 0)
		return 0;
	return n.toString(16);
}

exports.Bin2Dec = function(n){
	if(!this.checkBin(n))
		return 0;
	return parseInt(n,2).toString(10);
}

exports.Bin2Hex = function(n){
	if(!this.checkBin(n))
		return 0;
	return parseInt(n,2).toString(16);
}

exports.Hex2Bin = function(n){
	if(!this.checkHex(n))
		return 0;
	return parseInt(n,16).toString(2);
}

exports.Hex2Dec = function(n){
	if(!this.checkHex(n))
		return 0;
	return parseInt(n,16).toString(10);
}


exports.Hex2Ascii = function(hexx) {
    var hex = hexx.toString();//force conversion
    var str = '';
    for (var i = 0; i < hex.length; i += 2)
        str += String.fromCharCode(parseInt(hex.substr(i, 2), 16));
    return str;
}


exports.replaceAt = function(str, index, character) {
		var str = str.toString();//force conversion
		return str.substr(0, index) + character + str.substr(index+character.length);
}