Introduction to comparison operators >, <, >=, <= in JavaScript_javascript skills

Same as the == operator, the comparison operators (>, <, >=, <=) can convert the object into a string or number before comparison - for number, compare the size of the value; For strings, compare the order in which characters appear in the encoding table. What is different from the == operator is that == will first convert the Date object into a string before comparison, while the comparison operator will first convert all objects including Date into numbers before comparison. The rules for comparative judgment are as follows:

1. If there is an object on both sides of the operator, convert it into a number; if it cannot be converted into a number, convert it into a string.
2. After conversion, if both sides of the operator are strings, string comparison will be performed; otherwise, as long as number appears on one side, numerical comparison will be performed.
3. If NaN appears on both sides of the operator, return false.
4.0 is equal to -0.

Experiment

Copy code The code is as follows:

//In comparison, Date object is converted to number
var d = new Date();
var s1 = "Thu Mar 27 2008 14:57:11 GMT 0800 (CST)";
var s2 = "Thu Mar 27 2099 14:57:11 GMT 0800 (CST)";
var n1 = d.valueOf() - 1000;
var n2 = d.valueOf() 1000;
console.log(d > s1);//false, d is converted to number, and that number is further converted to string. It is a string comparison here.
console.log(d > s2);//false
console.log(d > n1);//true
console.log(d > n2);//false

console.log("11" > 3);//true

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