function _comma(number) { let res = '' let count = 0 const negative = number < 0 ? '-' : '' number = Math.abs(number).toString() for (let i = number.length - 1; i >= 0; i--) { count += 1 res = number[i] + res if (count % 3 === 0 && i !== 0 && number[i] !== '.') { res = ',' + res } } return negative + res } console.log(_comma(-123456789.89)) // -123,456,789.89 console.log(_comma(123456789.89)) // 123,456,789.89 console.log(_comma(123456789)) // 123,456,789 console.log(_comma(-123)) // -123 console.log(_comma(1234)) // 1,234
function _comma(number) { // 补全代码 let q = number.toString().split('') let sum = 0 var arr = [] for (let i = q.length - 1; i >= 0; i--) { sum++ if (sum != 4) { arr.unshift(q[i]) } else { if (q[i] != '-') { arr.unshift(',') sum = 1 } arr.unshift(q[i]) } } return arr.join('') }
// 提供一个思路,是可以封装的 function _comma(number) { // 补全代码 let newNumber = number.toString() let n = Math.floor(newNumber.split('').length / 3) if(Math.abs(number) < 1000){ return number.toString() }else if(n == 1){ return `${newNumber.slice(0,-3)},${newNumber.slice(-3)}` }else if((n == 2)){ return `${newNumber.slice(0,-6)},${newNumber.slice(-6,-3)},${newNumber.slice(-3)}` } }
function _comma(number) { // 补全代码 let zf if (number < 0) { zf = true } number = Math.abs(number) number = number.toString() number = number.split('') for (i = number.length - 2; i > 1; i = i - 3) { console.log('', number) number.splice(i - 1, 0, ',') } if (zf) { number.unshift('-') } return number.join('') }
function _comma(number) { if (number < 0) { return number.toString(); } let str = number.toString(); // 补全代码 let index = str.length - 1; let res = ""; for(; index >= 2; index -= 3) { let temp = index; res += str.charAt(temp--); res += str.charAt(temp--); res += str.charAt(temp); res += ","; } if(index >= 0) { while(index >= 0) { res += str.charAt(index--); } } return res.split("").reverse().join(""); }
<script type="text/javascript"> function _comma(number) { // 补全代码 let numStr = String(number); // 采用递归 // 如果是负数 小于等于4结束 整数 小于等于3结束 if (numStr.length <= 3 || (numStr.startsWith("-") && numStr.length <= 4)) { return numStr; } // 取后三位 let endTemp = numStr.slice(-3); // 去掉后三位 let startTemp = numStr.slice(0, -3); // 采用递归 return _comma(startTemp) + ',' + endTemp; } </script>
<!DOCTYPE html> <html> <head> <meta charset=utf-8> </head> <body> <script type="text/javascript"> function _comma(number) { // 补全代码 if(number>-999 && number < 999){ return String(number); } let num = String(number); var count =0; let resnum = new Array(); for(let i=num.length-1;i>=0;i--){ if(count == 3){ count =0; resnum.push(','); } resnum.push(num[i]); count++; } return resnum.reverse().join(''); } </script> </body> </html>
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <style> /* 填写样式 */ </style> </head> <body> <!-- 填写标签 --> <script type="text/javascript"> // 填写JavaScript function _comma(number) { // 补全代码 const arr = Math.abs(number).toString().split(''); for (let i = arr.length - 3; i > 0; i = i - 3) { arr.splice(i, 0, ','); } const commaNum = arr.join(''); return number > 0 ? commaNum : `-${commaNum}`; } </script> </body> </html>