在Lua中格式化整数

本文介绍了在Lua中格式化整数的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想将数字格式化为类似于 1,234 或 1,234,432 或 123,456,789 的数字，您就明白了.我尝试这样做，如下所示:

I'd like to format a number to look like 1,234 or 1,234,432 or 123,456,789, you get the idea. I tried doing this as follows:

function reformatint(i) local length = string.len(i) for v = 1, math.floor(length/3) do for k = 1, 3 do newint = string.sub(mystring, -k*v) end newint = ','..newint end return newint end

如您所见，一次失败的尝试，我的问题是我无法弄清楚错误是什么，因为我正在其中运行该程序的程序拒绝向我报告错误.

As you can see, a failed attempt, my problem is that I can't figure out what the error is because the program I am running this in refuses to report an error back to me.

推荐答案

这是一个将负数和小数部分都考虑在内的函数:

Here's a function that takes negative numbers, and fractional parts into account:

function format_int(number) local i, j, minus, int, fraction = tostring(number):find('([-]?)(%d+)([.]?%d*)') -- reverse the int-string and append a comma to all blocks of 3 digits int = int:reverse():gsub("(%d%d%d)", "%1,") -- reverse the int-string back remove an optional comma and put the -- optional minus and fractional part back return minus .. int:reverse():gsub("^,", "") .. fraction end assert(format_int(1234) == '1,234') assert(format_int(1234567) == '1,234,567') assert(format_int(123456789) == '123,456,789') assert(format_int(123456789.1234) == '123,456,789.1234') assert(format_int(-123456789.) == '-123,456,789') assert(format_int(-123456789.1234) == '-123,456,789.1234') assert(format_int('-123456789.1234') == '-123,456,789.1234') print('All tests passed!')