一般在JavaScript中实现千分符，是使用切割+连接一顿操作
这里尝试一下使用正则快速实现千分符
1 let num0 = ‘12‘ 2 let num1 = ‘123‘ 3 let num2 = ‘1234‘ 4 let num3 = ‘123456789‘ 5 let num4 = ‘1234567890‘ 6 let num5 = ‘12345678901‘ 7 let num6 = ‘123456789012‘ 8 let num7 = ‘1234567890123‘ 9 10 11 let r0 = num0.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 12 let r1 = num1.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 13 let r2 = num2.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 14 let r3 = num3.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 15 let r4 = num4.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 16 let r5 = num5.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 17 let r6 = num6.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 18 let r7 = num7.replace(/(\d{1,3})(?=(\d{3})+$)/g, ‘$1,‘) 19 20 console.log(r0) // 12 21 console.log(r1) // 123 22 console.log(r2) // 1,234 23 console.log(r3) // 123,456,789 24 console.log(r4) // 1,234,567,890 25 console.log(r5) // 12,345,678,901 26 console.log(r6) // 123,456,789,012 27 console.log(r7) // 1,234,567,890,123
原文：https://www.cnblogs.com/linjunfu/p/10761504.html