Passing argument to async callback function: Sharepoint 2010 ECMA Script

Hi
Below is the example which shows how to pass the argument to the async call back function through the ECMA script in SharePoint 2010. There might be need for developer to know for which call I am getting the success message and do some event logging or something. Below example shows how that can be achieved.

<script language="ecmascript" type="text/ecmascript">

        var fieldCollection;

        var field;

        var list;

        function getFieldType() {

            var clientContext = SP.ClientContext.get_current();

            if (clientContext != undefined && clientContext != null) {

                var webSite = clientContext.get_web();

                this.list = webSite.get_lists().getByTitle("PeopleList");

                this.fieldCollection = list.get_fields();

                this.field = fieldCollection.getByTitle("Title");

                clientContext.load(this.field);

var myCallBack = Function.createCallback(OnLoadSuccess, this.field);

                clientContext.executeQueryAsync( Function.createDelegate(this, myCallBack), Function.createDelegate(this, this.OnLoadFailed));

alert('In main function... ' + field.get_title());

            }

        }

        function OnLoadSuccess(sender, args, field1) {

            alert('In callback success... ' + field1.get_title());

        }

        function OnLoadFailed(sender, args) {

            alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());

        }</script><input id="btnGetFieldType" onclick="getFieldType()" type="button" value="Get Field Type"/>