jQuery仅评估最后一个单词

How would I make jJvascript/jQuery evaluate the last word entered?

Example (doe ra fa la si do) Only evaluate do

Very similar to Google's search box. I want only to evaluate after a space and have that word searched for with an Ajax call.

Here's the code I tried:

$(document).ready(function() {

    ajaxcall();
    var x = setInterval(ajaxcall, 1000);

    function ajaxcall() {
        var nameid = $('#word').val();
        if (nameid.match(/^\s*$/)) {
            // nothing, or nothing but whitespace
        } else {
            $.get('mysqlquery.php?id=' + nameid, function(data) {
                $('#loadbox').append(data + ' ');
            });
        }
    }
});​

 $(document).ready(function(){

    ajaxcall();
    var x = setInterval(ajaxcall,1000);

function ajaxcall(){
    var nameid = $('#word').val().split(' ');
    nameid = nameid[nameid.length-1];
        if (nameid.match(/^\s*$/)) {
        // nothing, or nothing but whitespace
    } else {
        $.get('mysqlquery.php?id='+nameid, function(data){
        $('#loadbox').append(data+' ');     
              });
        }
  }
});

This should return the last word of the string:

var str = 'doe ra fa la si do',
    patt = /[^\s]*$/;
alert(str.match(patt)); // Returns `do`

Try using .split() to convert the string into an array and then using .pop() to return the last element in the array:

function lastWord(subject)
{
    var ar = subject.split(" ");
    return ar.pop();
}

lastWord("some amazing sentence"); // sentence