标签：dex XML utf-8 com https block ret 前置 for
众所周知JavaScript中的数字是没有前置0的，因此需要我们自己进行操作来添加前置0，而且还得转换成字符串。
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"<head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>JavaScript 数字前补“0”</title><body><script> //迭代方式实现 function padding1(num, length) { for(var len = (num + "").length; len < length; len = num.length) { num = "0" + num; } return num; } //递归方式实现 function padding2(num, length) { if((num + "").length >= length) { return num; } return padding2("0" + num, length) } //转为小数 function padding3(num, length) { var decimal = num / Math.pow(10, length); //toFixed指定保留几位小数 decimal = decimal.toFixed(length) + ""; return decimal.substr(decimal.indexOf(".")+1); } //填充截取法 function padding4(num, length) { //这里用slice和substr均可 return (Array(length).join("0") + num).slice(-length); } //填充截取法 function padding5(num, length) { var len = (num + "").length; var diff = length - len; if(diff > 0) { return Array(diff).join("0") + num; } return num; } function test(num, length) { document.write(padding1(num, length)); document.write("<br>"); document.write(padding2(num, length)); document.write("<br>"); document.write(padding3(num, length)); document.write("<br>"); document.write(padding4(num, length)); document.write("<br>"); document.write(padding5(num, length)); document.write("<br>"); } test(123, 10); test(1234567890123, 10);</script></body></html> |
输出
0000000123
0000000123
0000000123
0000000123
000000123
1234567890123
1234567890123
4567890123
4567890123
1234567890123
标签：dex XML utf-8 com https block ret 前置 for
原文地址：https://www.cnblogs.com/raineliflor/p/10397074.html
