Javascript 左填充字符串的最简单内联方法
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/13859538/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Simplest inline method to left pad a string
提问by Daniel Reis
Possible Duplicate:
Is there a JavaScript function that can pad a string to get to a determined length?
What's the simplest way to left pad a string in javascript?
在javascript中左填充字符串的最简单方法是什么？
I'm looking for an inline expression equivalent to mystr.lpad("0", 4): for mystr='45'would return 0045.
我正在寻找一个相当于mystr.lpad("0", 4): for will mystr='45'return的内联表达式0045。
回答by Daniel Reis
Found a simple one line solution:
找到了一个简单的单行解决方案：
("0000" + n).slice(-4)
If the string and padding are in variables, you would have:
如果字符串和填充在变量中，您将有：
mystr = '45'
pad = '0000'
(pad + mystr).slice(-pad.length)
Answer found here, thanks to @dani-p. Credits to @profitehlolz.
答案在这里找到，感谢@dani-p。归功于@profitehlolz。
回答by Kevin Bowersox
function pad(value, length) {
return (value.toString().length < length) ? pad("0"+value, length):value;
}
回答by xdazz
Something like below:
像下面这样：
String.prototype.lpad = function(padString, length) {
var str = this;
while (str.length < length)
str = padString + str;
return str;
}
console.log('45'.lpad('0', 4)); // "0045"
