ESRI has a geocoder widget with autocomplete here, and it's built into 3.4 I believe.Here is an autocomplete I wrote a while back with jQuery UI and an ESRI query endpoint: $('#txtSearch').autocomplete({
source: function (request, response) {
$.ajax({
url: "http://someurl/ArcGIS/rest/services/someservice/MapServer/0/query",
dataType: "jsonp",
data: {
where: "FIELDNAME LIKE '" + request.term.replace(/\'/g, '\'\'') + "%'",//makes single quotes into double for sql
outFields: "FIELDNAME",
returnGeometry: false,
f: "pjson"
},
success: function (data) {
if (data.features) {
response($.map(data.features.slice(0, 9), function (item) {//only display first 10
return { label: item.attributes.FIELDNAME, value: item.attributes.FIELDNAME }
}));
}
}
});
},
minLength: 3,
select: function (event, ui) {
this.blur();
var query = new esri.tasks.Query();
query.returnGeometry = true;
query.outFields = ["*"];
query.where = "FIELDNAME = '" + ui.item.value.replace(/\'/g, '\'\'') + "'";
queryTask.execute(query,
fxns.showQueryResult,
function (e) {
alert(e.toString());
}
);
}
});