<input type="text" name="username" id="username" onkeyup="search_func(this.value);"  /><em id="mfee">em>
function search_func(value){
 $.post("/xxx.php", { q: "action/cash_news", username:value},function (result){
        var r = "可用金额"+result+"元";
        $("#mfee").html(r);
        $("#moneyss").val(result);    
    });
}
script>