Why Does '2' > '10' in Javascript?

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Javascript String/Integer Comparison Quandary: Why "2" > "10"?

Javascript programming has a peculiar quirk with string and integer comparisons. While one might assume that numerical strings are treated as integers, this is not always the case, leading to unexpected results.

Consider the following perplexing code:

console.log("2" > "10");

To the astonishment of many, this code evaluates to true. Why would "2" be greater than "10"?

The underlying issue lies in Javascript's inherent treatment of strings and integers. When comparing two strings, Javascript performs a lexicographical comparison based on their Unicode code points. In this case, the ASCII code point for "2" (50) is less than the code point for "10" (56), resulting in "2" being considered "less than" "10" in a string comparison.

To resolve this dilemma and accurately compare numerical values as integers, it is crucial to manually parse the string into an integer. This can be achieved using the parseInt function, which takes a string and a base radix as arguments.

For instance, to convert the string "2" to an integer and perform a meaningful comparison with "10":

alert(parseInt("2", 10) > parseInt("10", 10));

This code correctly evaluates to false, as "2" is indeed less than "10" when both are treated as integers.

By employing meticulous string parsing, one can avoid the pitfalls of Javascript's confusing string/integer comparison behavior and ensure reliable numerical comparisons.

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