Javascript添加数字就好像它们是一个字符串[重复](Javascript adding numbers as if they were a string [duplicate])

 
 
 这个问题在这里已有答案： 
 
 
 
  
 Javascript（+）符号连接而不是给出变量的总和 12个答案 
 
 
 
 
 我第一次玩饼干，我已经完成了部分保存。 我正在保存的数据是数字，这些nubers最重要的部分是我可以添加，减去等等。 但是，当我尝试将一个数字添加到我保存的参数之一时，它会将它们添加为文本。 
 
 示例：我有一个名为value的cookie，当我想要这个值时，我使用Jeffery To找到的脚本，如下所示： 
 
function readCookie(name) {
    return (name = new RegExp('(?:^|;\\s*)' + ('' + name).replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&') + '=([^;]*)').exec(document.cookie)) && name[1];
}
 
 我收集了这个cookie后，我想添加一个。 让我们说这个值等于9，它应该是这样的： value + 1 = 10 。 简单的数学。 然而它给了我91 。 为什么这样做？ 我知道这是因为它认为数字是一串文字，但我怎么能让它像数字一样？ 
 
 解决方案阅读完评论后，我了解到我需要将我的value放在parseInt() 。 所以我只是修改了功能说： 
 
function readCookie(name) {
        return parseInt((name = new RegExp('(?:^|;\\s*)' + ('' + name).replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&') + '=([^;]*)').exec(document.cookie)) && name[1]);
    }

 
 
This question already has an answer here:
 
 
 
  
 Javascript (+) sign concatenates instead of giving sum of variables  14 answers  
 
 
 
 
I have been playing around with cookies for the first time, and I have saving part of it completed. The data I'm saving are numbers and the most important part of these nubers is that I can add, subtract and so on with these. However when I try to add a number to one of my saved parametres it adds them as if they were text. 
 
Example: I have a cookie called value, and when I want this value I use a script I found by Jeffery To that looks like this: 
 
function readCookie(name) {
    return (name = new RegExp('(?:^|;\\s*)' + ('' + name).replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&') + '=([^;]*)').exec(document.cookie)) && name[1];
}
 
After I have collected this cookie I want to add one to it. Lets say that value equals nine, when it should look like this: value + 1 = 10. Simple math. However it gives me this 91. Why does it do this? I know that it is because it thinks the numbers are a string of text, but how can I get this to behave like numbers?
 
Solution After reading the comments I learned that i needed to put my value inside a parseInt(). So i simply modified the funtion to say:
 
function readCookie(name) {
        return parseInt((name = new RegExp('(?:^|;\\s*)' + ('' + name).replace(/[-[\]{}()*+?.,\\^$|#\s]/g, '\\$&') + '=([^;]*)').exec(document.cookie)) && name[1]);
    }

原文：https://stackoverflow.com/questions/40661354