Google Maps Geocoding a string

This will change the codeAddress function to take an argument and geocode that argument. If you pass the Ireland variable as the argument it will geocode "Dublin".

var Ireland = "Dublin";

function initialize() 
{
  geocoder = new google.maps.Geocoder();
  var latlng = new google.maps.LatLng(53.3496, -6.3263);
  var mapOptions = 
  {
    zoom: 8,
    center: latlng
  }
  map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
  codeAddress(Ireland);//call the function
}

function codeAddress(address) 
{
  geocoder.geocode( {address:address}, function(results, status) 
  {
    if (status == google.maps.GeocoderStatus.OK) 
    {
      map.setCenter(results[0].geometry.location);//center the map over the result
      //place a marker at the location
      var marker = new google.maps.Marker(
      {
          map: map,
          position: results[0].geometry.location
      });
    } else {
      alert('Geocode was not successful for the following reason: ' + status);
   }
  });
}

enter image description here

code snippet:

var Ireland = "Dublin";

function initialize() {
  geocoder = new google.maps.Geocoder();
  var latlng = new google.maps.LatLng(53.3496, -6.3263);
  var mapOptions = {
    zoom: 8,
    center: latlng
  }
  map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
  codeAddress(Ireland); //call the function
}

function codeAddress(address) {
  geocoder.geocode({
    address: address
  }, function(results, status) {
    if (status == google.maps.GeocoderStatus.OK) {
      map.setCenter(results[0].geometry.location); //center the map over the result
      //place a marker at the location
      var marker = new google.maps.Marker({
        map: map,
        position: results[0].geometry.location
      });
    } else {
      alert('Geocode was not successful for the following reason: ' + status);
    }
  });
}
html,
body,
#map-canvas {
  height: 100%;
  width: 100%;
  padding: 0;
  margin: 0;
}
<div id="map-canvas"></div>
<!-- Replace the value of the key parameter with your own API key. -->
<script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk&callback=initialize" async defer></script>

Just Try with this.

 <!doctype html>
    <html lang="en">
    <head>
    <meta charset="utf-8">
    <title>Google Map Address</title>
    <script src="http://code.jquery.com/jquery-latest.min.js" type="text/javascript"></script>
    <script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>

    <script type="text/javascript">

            var geocoder = new google.maps.Geocoder();
    var address = "Dublin";

    geocoder.geocode( { 'address': address}, function(results, status) {

      if (status == google.maps.GeocoderStatus.OK) {
        var latitude = results[0].geometry.location.lat();
        var longitude = results[0].geometry.location.lng();


        initialize(latitude,longitude);

                } 

        }); 


    function initialize(latitude,longitude) {
        var latlng = new google.maps.LatLng(latitude,longitude);

        var myOptions = {
          zoom: 14,
          center: latlng,
          mapTypeId: google.maps.MapTypeId.ROADMAP,
          mapTypeControl: false
        };
        var map = new google.maps.Map(document.getElementById("map_canvas"),myOptions);

        var marker = new google.maps.Marker({
          position: latlng, 
          map: map, 
            title:"location : Dublin"
        }); 
      }


</script>

    </head>
    <body>

    <h2>Google Map Address</h2>

    <div id="map_canvas" style="width:710px; height:300px"></div>   

            </body>
    </html>