Javascript compare numbers as strings

Question

I wish to compare two strings in javascript. I am using localeCompare method but the output is not as expected

116457 < 3085
false
"116457" < "3085"
true
"116457".localeCompare("3085")
-1

Output in second and third case is not as expected.

I know it sorts in Lexicographical order but still I am having trouble understanding why is it so and how should I overcome this.

Any help would be appreciated.

• user5734311: "1" comes before "3", so any String starting with "1" comes before any other string starting with "3". You say you know this but have trouble understanding why. Would you agree that "a" < "c"?
• Flo: Those strings are always integers ? If yes, why won't you cast it using parseInt(str) ?
• user3807691: Actually no. In the scenario I am handling, they won't always be integers
• jmrk: re "how should I overcome this": if you want suggestions for solutions, you'll have to be a lot more specific on what the requirements are. What pattern do your inputs have, and how do you want them sorted? You said "c-3085" can occur; can "a-5" and "b-1" and "a-b+7-c+1" occur too, and how should they sort?
• user3807691: Thanks everyone for the help. I will be writing my own function!

Answer 1

If you want to compare them without converting them to numbers, you can set numeric: true in the options parameter

console.log(
 "116457".localeCompare("3085", undefined, { numeric: true })
)
console.log(
 "116457".localeCompare("3085")
)

Answer 2

If 116457 were a word, it would come before 3085 in a dictionary.

Consider a dictionary with

• "applicative" (a long word starting with "a", c.f. a long digit string starting with "1")
• "copy" (a short word starting with "c", c.f. a shorter digit string starting with "3").

• user3807691: Okay. Makes sense.
• user3807691: But how do I overcome this? (I don't want to convert it to a number)
• Jonas Wilms: Convert it to a number? "I don't want to" ... and why?
• user3807691: I basically "can't" cast it using parseInt(str) or Number(str) as in the scenario I am handling, it doesn't always gets integers. There are cases I get strings as well. Example : "c-116457" and "c-3085"
• jmrk: Well, if you have complex strings where various substrings have specific meaning, then you'll have to write your own comparator function that takes all of that into acount. It may be more efficient to represent your data differently, e.g. as objects with a bunch of properties rather than as a string.