Question

该算法在javascript中的字符串比较背后起作用，例如

'bc' > 'ac' = true/false ?
'ac' > 'bc' = true/false ?

Answer 1

这是使用ECMA-5中的The Abstract Relational Comparison Algorithm计算的。相关部分引用如下。

4. Else, both px and py are Strings
    a) If py is a prefix of px, return false. (A String value p is a prefix 
       of String value q if q can be the result of concatenating p and some
       other String r. Note that any String is a prefix of itself, because 
       r may be the empty String.)
    b) If px is a prefix of py, return true.
    c) Let k be the smallest nonnegative integer such that the character 
       at position k within px is different from the character at position 
       k within py. (There must be such a k, for neither String is a prefix 
       of the other.)
    d) Let m be the integer that is the code unit value for the character 
       at position k within px.
    e) Let n be the integer that is the code unit value for the character 
       at position k within py.
    f) If m < n, return true. Otherwise, return false.

Answer 2

字符串逐字符进行比较，因此第一个字母最重要，因此

'bc' > 'ac' = true/false ? => true
'ac' > 'bc' = true/false ? => false

如果第一个字母相等，那么第二个字母将被比较，依此类推，直到其中一个字母大于或小于或等于。

Answer 3

javascript会将字母转换为ascii代码并首先比较第一个字符。

您可以在此处查看ascii代码表http://www.kerryr.net/pioneers/ascii2.htm

来自你的问题

'bc' > 'ac' // because b > a

Answer 4

不仅在javascript中，简单来说，所有字符串比较算法都将遵循字典顺序或字典顺序，这意味着它将逐个字符地检查每个字符，如果有不匹配，则可以决定结果

True: 
ant < any
aaa < aab 
aab < b 
b < baa

字符串比较如何在JavaScript中运行？

4 个答案: