place.address_components[i].types[j] == 'postal_code') code example

Example 1: place.address_components[i].types[0];

var componentForm = {
    street_number: 'short_name',
    route: 'long_name',
    locality: 'long_name',
    administrative_area_level_1: 'short_name',
    postal_code: 'short_name'
};

var place = searchaddress.getPlace();

for (var i = 0; i < place.address_components.length; i++) {

    var addressType = place.address_components[i].types[0];

    if (componentForm[addressType]) {

        if (addressType == 'street_number') {
            var streetNumber = place.address_components[i][componentForm[addressType]];
        }

        if (addressType == 'route') {
            var route = place.address_components[i][componentForm[addressType]];
        }

        if (addressType == 'locality') {
            var locality = place.address_components[i][componentForm[addressType]];
        }

        if (addressType == 'administrative_area_level_1') {
            var state = place.address_components[i][componentForm[addressType]];
        }

        if (addressType == 'postal_code') {
            var zipcode = place.address_components[i][componentForm[addressType]];
        }

    }

}

document.getElementById('fullAddress').value = streetNumber + ' ' + route + ', ' + locality + ', ' + state + ' ' + zipcode;

Example 2: place.address_components[i].types[0];

<div id="fullAddress"></div>