求教jquery ajax逐条处理数据怎么写？

<input type="text" name="chaxun" id="chaxun">
<button id="button" onclick="search()">查询</button>
 
<script src="jquery.js"></script>
<script>
    var dataCount = 0;
    function search()
    {
        dataCount = 0;
        $('#chaxun').attr('readonly', 'readonly');
        $('#button').attr('disabled', 'disabled');
        ajax(
            'post', 'mysql.php', null,
             function(response) {
                if (response.lenth > 0) {
                    dataCount = response.length;
                    for (var index in response) {
                        completeData({chaxun: response[index]});
                    }
                }
                 
                if (dataCount == 0) {
                    $('#chaxun').removeAttr('readonly');
                    $('#button').removeAttr('disabled');                    
                }
                 
             }, error
        );
    }
     
    function completeData(data)
    {
        ajax(
            'post', 'demo.php', data,
             function(response) {
                if (dataCount > 0) {
                    dataCount--;
                }
            }, error 
        );
    }
     
    function error(response)
    {
        if (response.status == 503) {
            alert('服务器超时，请稍后重试。');
        }
    }
     
    function ajax(type, url, data, cbfOk, cbfError)
    {
        $.ajax({
            type: type,
            url: url,
            async: false,
            data: data,
            dataType: 'json',
            success: function(response)
            {
                if (typeof cbfOK == 'function') {
                    return cbfOk(response);
                }               
                return true;
            },
            error:function(response)
            {
                if (typeof cbfError == 'function') {
                    return cbfError(response);
                }
                return false;
            }
        });     
    }
</script>