Parse common lat/lng formats

parse-latlng.js

var parseLatLng = (function() 
{
    var matchLocDecimal = /^\s*(-?\d+)(\.\d+)?\s*°?\s*(N|S)?(,|\s)+(-?\d+)(\.\d+)?\s*°?\s*(E|W)?\s*$/;
    var matchLocDegrees = /^\s*(-?\d+)°?\s*((\d+)(\.\d+)?'?)?\s*(N|S)?(,|\s)+(-?\d+)°?\s*((\d+)(\.\d+)?'?)?\s*(E|W)?\s*$/;
    var matchLocCompass = /^\s*(-?\d+)°?\s*((\d+)('|\s)+)?\s*((\d+)(\.\d+)?(''|")?)?\s*(N|S)?(,|\s)+(-?\d+)°?\s*((\d+)('|\s)+)?\s*((\d+)(\.\d+)?(''|")?)?\s*(E|W)?\s*$/;
    
    return function(val)
    {
        var matches,
            lat, lng,
            flipLat = false, flipLng = false;

        if (matches = val.match(matchLocDecimal)) {

            lat = parseInt(matches[1] || 0) + parseFloat(matches[2] || 0);
            lng = parseInt(matches[5] || 0) + parseFloat(matches[6] || 0);
            flipLat = matches[3] === 'S';
            flipLng = matches[7] === 'W';

        } else if (matches = val.match(matchLocDegrees)) {

            lat = parseInt(matches[1] || 0) + (parseInt(matches[3] || 0) / 60) + (parseFloat(matches[4] || 0) / 3600);
            lng = parseInt(matches[7] || 0) + (parseInt(matches[9] || 0) / 60) + (parseFloat(matches[10] || 0) / 3600);
            flipLat = matches[5] === 'S';
            flipLng = matches[11] === 'W';

        } else if (matches = val.match(matchLocCompass)) {

            lat = parseInt(matches[1] || 0) + (parseInt(matches[3] || 0) / 60) + (parseFloat(matches[5] || 0) / 3600);
            lng = parseInt(matches[11] || 0) + (parseInt(matches[13] || 0) / 60) + (parseFloat(matches[15] || 0) / 3600);
            flipLat = matches[9] === 'S';
            flipLng = matches[19] === 'W';

        } else {

            return null;

        }

        if (flipLat) {
            lat *= -1;
        }
        if (flipLng) {
            lng *= -1;
        }

        return [lat, lng];
    };
})();