对 Javascript 变量求和（实际上是字符串）
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Sum Javascript variables (strings, actually)
提问by Hugo
I have three divthat contain a number.
我有三个div包含一个数字。
<div class="a">10</div>
<div class="b">20</div>
<div class="c">30</div>
I get the number inside each one with jQuery .html().
我用 jQuery 得到每个里面的数字.html()。
var val_1 = $('.a').html(),
val_2 = $('.b').html(),
val_3 = $('.c').html();
How can I sum them?
我该如何总结它们？
This do not work as expected:
这不能按预期工作：
var total = val_1 + val_2 + val_3;
Since returned 102030, when I expected 60.
自从返回 102030，当时我预计 60。
回答by floribon
First, since you want only the content of your divs, you'd better use $('.x').text()instead of $('.x').html().
首先，因为只需要你的div的内容，你最好使用$('.x').text()代替$('.x').html()。
Now what's happening is that you're additioning strings, ie concatening them: '1' + '2' + '3soleil' === '123soleil'.
现在发生什么事是你是additioning串，即concatening他们：'1' + '2' + '3soleil' === '123soleil'。
You want to parse them into numbers, which is done with
你想把它们解析成数字，这是用
Number(val1) + Number(val2) + Number(val3)
If you know they're integers, you can more safely use Number.parseInt(val, 10)(the second variable of that function, called radix, is the mathematic base of your number. It's most likely a decimal number (10), but could be hexadecimal (16), boolean number (2), etc)
如果您知道它们是整数，则可以更安全地使用Number.parseInt(val, 10)（该函数的第二个变量，称为基数，是数字的数学基数。它很可能是十进制数 (10)，但也可能是十六进制数 (16)，布尔数 (2) 等）
回答by Travis J
You could group them, use each to iterate, and total their parseInt numbers
您可以将它们分组，使用每个进行迭代，并总计它们的 parseInt 数
var val = 0;
$('.a, .b, .c').each(function(){
val += parseInt(this.innerHTML,10);
});
alert(val);
回答by MamaWalter
回答by Kylok
Use parseInt()on each variable; right now it's treating them as strings and concatenating them.
parseInt()在每个变量上使用；现在它将它们视为字符串并将它们连接起来。
回答by jmiller
You need to parse the string value returned from .html() as an int using parseInt().
您需要使用 parseInt() 将从 .html() 返回的字符串值解析为 int。
var val_1 = parseInt($('.a').html())
回答by Hyman Tuck
If you don't want to type (var + var), you could do the following.
如果您不想键入 (var + var)，则可以执行以下操作。
Firstly, the issue in your code was that your variables were interpreted as strings, we can force the INT data-type like, so.
首先，您代码中的问题是您的变量被解释为字符串，我们可以强制使用 INT 数据类型，所以。
val_1 = parseInt($('.a').html()),
val_2 = parseInt($('.b').html()),
val_3 = parseInt($('.c').html());
Then we aggregate the variables into a tidy array, then perform the .reduce()function, which is a sum function.
然后我们将变量聚合成一个整齐的数组，然后执行.reduce()函数，它是一个求和函数。
var aggregate = array(val_1, val_2, val_3);
aggregate.reduce(function(a,b){return a + b})
