更改单价和数量的时候总价会改变

<ext:FormRow >
<Items>
<ext:NumberBox ID="sItemMoney" Label="单价" runat="server" DecimalPrecision="2" CompareType="Float">
<Listeners>
<ext:Listener Event="change" Handler="onTextBoxChange"/>
</Listeners>
</ext:NumberBox>

<ext:NumberBox ID="sTotalMoney" Label="总价" runat="server" DecimalPrecision="2" CompareType="Float" Enabled="false"/>

</Items>
</ext:FormRow>

<ext:NumberBox ID="sQuantity" Label="数量" runat="server" ShowRedStar="True" Required="True" DecimalPrecision="2" CompareOperator="GreaterThan" CompareValue="0" CompareType="Float">
<Listeners>
<ext:Listener Event="change" Handler="onTextBoxChange" />
</Listeners>
</ext:NumberBox>

function onTextBoxChange() {

F(ItemMoneyClientID).setValue(F(UnitPriceClientID).getValue() * F(QuantityClientID).getValue());

}