如何在逗號後用3位數字解析浮點數？

Question

我有浮點數

var distance = 3.643462215; 

我想要的結果是這樣的：

我的距離是3公里，643米

Answer 1

讓我們假設distance是肯定的浮動 - 如果是字符串，請執行：distance = parseFloat(distance)

您可以嘗試與：

distance.toFixed(3); 

它給你3.643;

distance.toFixed(3).split('.'); 

它返回：你可以用它拆分分隔值

["3", "643"] 

所以得到它運行：

var distance = 3.643462215, 
    parts = distance.toFixed(3).split('.'), 
    output = 'my distance is ' + parts[0] + ' kilometers and ' + parts[1] + ' meters'; 

輸出：

"my distance is 3 kilometers and 643 meters" 

Answer 2

Math.round(distance * 1000)/1000 

Answer 3

var distance = 3.643462215; 

var reg = /(\d*)\.(\d{0,3})/; // using reg exp, because split won't work with float numbers 

var res = reg.exec(distance); 

console.log(res[1] + " Kilometers, " + res[2] + " Meters"); // 3 Kilometers, 643 Meters 

在劇本我（.之前和之後）的兩件與RegExp幫助分裂數，然後用結果操縱存儲在res可變

JSFiddle

Answer 4

var distance = 3.643462215; 

var n = Math.floor(distance); // KM part 

var m = Math.round((distance-n) * 1000); // meter part 

Answer 5

簡單的解決方案我可以建議是

<script type="text/javascript"> 
var distance = 3.643462215; 
var strDistance = distance.toString(); 

var km = strDistance.substr(0, strDistance.indexOf('.')); 
var mt = strDistance.substr(strDistance.indexOf('.')+1, 3); 

alert("my distance is "+km+" kilometers and "+mt+" meters"); 
</script>