DataGrid中实现输入数量和金额自动计算出总金额

<script language="javascript">

//四舍五入

Number.prototype.toFixed=function(len)

{

var add = 0;

var s,temp;

var l = this + "";

var start = l.indexOf(".");

if(l.substr(start+len+1,1)>=5)add=1;

var temp = Math.pow(10,len);

s = Math.floor(this * temp) + add;

return s/temp;

}

//实现计算金额

function count(obj)

{

var regInt = /^\d+$/;

var regMondy = /^(0|[1-9]\d*)$|^(0|[1-9]\d*)\.(\d+)$/;

// 找出TextBox

var objParent = obj.parentElement.parentElement;

var textBoxs = objParent.getElementsByTagName("input");

var TxtGoodsNum = null;

var TxtGoodsSinglePrice = null;

var TxtGoodsSumPrice = null;

for( var i=0;i < textBoxs.length;i ++)

{

if(textBoxs[i].id.indexOf("txtGoodsNum") != -1)

{

TxtGoodsNum = textBoxs[i];

}

else if(textBoxs[i].id.indexOf("txtGoodsSinglePrice") != -1)

{

TxtGoodsSinglePrice = textBoxs[i];

}

else if(textBoxs[i].id.indexOf("txtGoodsSumPrice") != -1)

{

TxtGoodsSumPrice = textBoxs[i];

}

}

if(!regInt.test(TxtGoodsNum.value))

{

alert("数量只能是数字，请您重新输入数量。");

return;

}

if(!regMondy.test(TxtGoodsSinglePrice.value))

{

alert("单价只能是数字，请您重新输入单价。");

return;

}

var GoodsNum = parseInt(TxtGoodsNum.value); //数量

var SinglePrice = parseFloat(TxtGoodsSinglePrice.value); //单价

var GoodsSumPrice = GoodsNum * SinglePrice;

TxtGoodsSumPrice.value = GoodsSumPrice.toFixed(3).toString();

}

</script>

调用：

<asp:TextBox id=txtGoodsNum onblur=count(this) runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Goods_Num") %>' Width="60px">