Relational operators (<, <=, >, >=)

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Example

When both operands are numeric, they are compared normally:

1 < 2        // true
2 <= 2       // true
3 >= 5       // false
true < false // false (implicitly converted to numbers, 1 > 0)

When both operands are strings, they are compared lexicographically (according to alphabetical order):

'a' < 'b'    // true
'1' < '2'    // true
'100' > '12' // false ('100' is less than '12' lexicographically!)

When one operand is a string and the other is a number, the string is converted to a number before comparison:

'1' < 2      // true
'3' > 2      // true
true > '2'   // false (true implicitly converted to number, 1 < 2)

When the string is non-numeric, numeric conversion returns NaN (not-a-number). Comparing with NaN always returns false:

1 < 'abc'    // false
1 > 'abc'    // false

But be careful when comparing a numeric value with null, undefined or empty strings:

1 > ''        // true
1 < ''        // false
1 > null      // true
1 < null      // false
1 > undefined // false
1 < undefined // false

When one operand is a object and the other is a number, the object is converted to a number before comparison.So null is particular case because Number(null);//0

new Date(2015)< 1479480185280            // true
null > -1                                //true
({toString:function(){return 123}}) > 122  //true

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2017-03-10
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