JavaScript if Statement .length 不起作用。为什么？
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JavaScript if Statement .length not working. Why?
提问by user3295521
I have this if statement i have came up with here:
我有我在这里提出的 if 语句：
var TotalMoney=0;
var Orbs=0;
if (TotalMoney.length==2) {
Orbs+=1;
}
What this code is supposed to do is if the the "TotalMoney" value digit length equals 2, example (the number 10 has 2 digits) then it will add 1 "Orb" to the "Orbs" value. Currently, it does nothing. There is HTML and CSS linked to this code but i figured the problem is in this code as it works fine for everything else. Please fix it as i have been trying for hours. Thanks!
这段代码应该做的是，如果“TotalMoney”值的数字长度等于 2，例如（数字 10 有 2 位数字），那么它将向“Orbs”值添加 1 个“Orb”。目前，它什么都不做。有 HTML 和 CSS 链接到此代码，但我认为问题出在此代码中，因为它适用于其他所有内容。请修复它，因为我已经尝试了几个小时。谢谢！
For my second question that i just found out with this code here:
对于我刚刚在此处使用此代码发现的第二个问题：
var totalMoney=0;
var orbs=0;
if (totalMoney.toString().length==2) {
orbs+=1;
}
This works on getting the number value digits as 2 digits long. The problem now is that once it reaches 10, every time that number goes up (10-99) all the way up, it will add 1 orb each time. I only want it to add 1 orb only when it gets to the 2 digit number (10) and stops adding 1 orb after it reaches it. How can i achieve this? Thanks!
这适用于将数值位数设为 2 位数。现在的问题是，一旦达到 10，每次该数字一路上升（10-99）时，每次都会增加 1 个球。我只希望它仅在达到 2 位数字 (10) 时才添加 1 个球体，并在到达后停止添加 1 个球体。我怎样才能做到这一点？谢谢！
回答by Scimonster
TotalMoneyis a number, so it doesn't have a lengthproperty. You can check the length of the number by first converting to a string: TotalMoney.toString().length.
TotalMoney是一个数字，所以它没有length属性。您可以通过首先转换为字符串来检查数字的长度：TotalMoney.toString().length。
回答by TiMirLAN
Number object in js has no length property, so TotalMoney.lengthreturn undefined.
js 中的 Number 对象没有 length 属性，所以TotalMoney.length返回undefined.
If you want count digits you may use this:
如果你想计算数字，你可以使用这个：
if (TotalMoney.toString().length == 2) {
Orbs+=1;
}
But if TotalMoneywill be negative, -1 for exmple, Orbs wil be incremented.
但是如果TotalMoney是负数，例如 -1，Orbs 将增加。
I think there are better way to find all 2-digits number:
我认为有更好的方法来查找所有 2 位数字：
if (TotalMoney>9 && TotalMoney<100) {
Orbs+=1;
}
回答by AmanS
TotalMoneyis numeric
so to find its length use this code
TotalMoney是数字所以要找到它的长度使用这个代码
TotalMoney.toString().length;
Instead of
代替
TotalMoney.length;
so try to modify your code as below:
所以尝试修改你的代码如下：
var TotalMoney=0;
var Orbs=0;
if (TotalMoney.toString().length==2) {
Orbs+=1;
}
回答by LexJacobs
here are some ideas and general comments on your code.
以下是对您的代码的一些想法和一般评论。
// recommended to start with lower case. upper case such as 'TotalMoney'
// is stylistically reserved for constructors.
var totalMoney=0;
// again - changing form Orbs to orbs;
var orbs=0;
// recommended to use '===' until you are more experienced with JavaScript and
// know about the 'gotchas' that '==' might produce.
// you will be able to check the length of totalMoney only after converting it to a string.
if (totalMoney.toString().length === 2) {
orbs+=1;
}
Finally, totalMoney of 0 will not add one to orbs. But totalMoney of 10, as you mentioned, will.
最后，totalMoney 为 0 不会向球体添加 1。但是正如你提到的，totalMoney 10 会。
回答by Ninad
Length is property of array & string.It can not be applied on other variables.
长度是数组和字符串的属性。它不能应用于其他变量。
If you want to count number of digits you can do
如果你想计算你可以做的位数
if(TotalMoney>9)
Or you can convert it to string then check it's length
或者您可以将其转换为字符串然后检查它的长度
if(TotalMoney.toSting().length>2)
