改一下这个:
document.getElementById("result").value = result;
=》
document.getElementById("result").value = result.tofixed(2);// 保留2位小数
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如下:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "
http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title> New Document </title>
</head>
<script type="text/javascript">
<!--
function jisuan(){
var num1 = document.getElementById("num1").value || 0;
var num2 = document.getElementById("num2").value || 0;
var num3 = document.getElementById("num3").value || 0;
var result = parseFloat(num1)+parseFloat(num2)+parseFloat(num3);
document.getElementById("result").value = result;
}
//-->
</script>
<body>
<input id="num1" onblur="jisuan()"/>+
<input id="num2" onblur="jisuan()" />+
<input id="num3" onblur="jisuan()" />=
<input id="result" readonly="true" />
</body>
</html>
追问
result;要怎么计算出来 。谢谢大侠!
追答var num1 = document.getElementById("num1").value || 0;
var num2 = document.getElementById("num2").value || 0;
var num3 = document.getElementById("num3").value || 0;
var result = parseFloat(num1)+parseFloat(num2)+parseFloat(num3);
document.getElementById("result").value = result;
不是很清楚了吗?
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