JS 如何实现ONBLUR自动计算？

Question

<script>
function filtervalue(o){
if(!o.value.match(/^[\+\-]?\d*?\.?\d*?$/))
o.value=o.t_value;
else
o.t_value=o.value;
if(o.value.match(/^(?:[\+\-]?\d+(?:\.\d+)?)?$/))
o.o_value=o.value
}
function compute(){
o1 = document.getElementById("huilv");
o2 = document.getElementById("shuliang0");
o3 = document.getElementById("money0");
o4 = document.getElementById("total");
filtervalue(o1);
filtervalue(o2);
filtervalue(o3);
o4.value = o1.value*o2.value*o3.value;
}
</script>
<table cellSpacing="1" cellPadding="4" width="100%" id="table1">
    <tr >
        <td>汇率</td>
        <td>数量</td>
        <td>金额</td>
        <td>合计</td>
    </tr>
    <tr >
        <td>
        <input onkeypress="compute()" onblur="compute()" onkeyup="compute()" size="4" value="1" name="huilv" id="huilv" o_value t_value></td>
        <td>
        <input onkeypress="compute()" onblur="compute()" onkeyup="compute()" size="5" value="1" name="shuliang0" id="shuliang0" o_value t_value></td>
        <td>
        <input onkeypress="compute()" onblur="compute()" onkeyup="compute()" size="5" value="0" name="money0" id="money0" o_value t_value></td>
        <td>
        <input onkeypress="compute()" onblur="compute()" onkeyup="compute()" size="5" value="0" name="total" id="total" o_value t_value></td>
    </tr>
</table>