How do I figure out if a variable 开发者_如何学Cis divisible by 2? Furthermore I need do a function if it is and do a different function if it is not.
Use modulus:
// Will evaluate to true if the variable is divisible by 2
variable % 2 === 0
Seriously, there's no jQuery plugin for odd/even checks?
Well, not anymore - releasing "Oven" a jQuery plugin under the MIT license to test if a given number is Odd/Even.
Source code is also available at http://jsfiddle.net/7HQNG/
Test-suites are available at http://jsfiddle.net/zeuRV/
(function() {
/*
* isEven(n)
* @args number n
* @return boolean returns whether the given number is even
*/
jQuery.isEven = function(number) {
return number % 2 == 0;
};
/* isOdd(n)
* @args number n
* @return boolean returns whether the given number is odd
*/
jQuery.isOdd = function(number) {
return !jQuery.isEven(number);
};
})();
You don't need jQuery. Just use JavaScript's Modulo operator.
You can use the modulus operator like this, no need for jQuery. Just replace the alerts
with your code.
var x = 2;
if (x % 2 == 0)
{
alert('even');
}
else
{
alert('odd')
}
You can do it in a better way (up to 50 % faster than modulo operator):
odd: x & 1 even: !(x & 1)
Reference: High Performance JavaScript, 8. ->Bitwise Operators
You can also:
if (x & 1)
itsOdd();
else
itsEven();
if (x & 1)
itIsOddNumber();
else
itIsEvenNumber();
Hope this helps.
let number = 7;
if(number%2 == 0){
//do something;
console.log('number is Even');
}else{
//do otherwise;
console.log('number is Odd');
}
Here is a complete function that will log to the console the parity of your input.
const checkNumber = (x) => {
if(number%2 == 0){
//do something;
console.log('number is Even');
}else{
//do otherwise;
console.log('number is Odd');
}
}
var x = 2;
x % 2 ? oddFunction() : evenFunction();
Please write the following code in your console:
var isEven = function(deep) {
if (deep % 2 === 0) {
return true;
}
else {
return false;
}
};
isEven(44);
Please Note: It will return true, if the entered number is even otherwise false.
Use Modulus, but.. The above accepted answer is slightly inaccurate. I believe because x is a Number type in JavaScript that the operator should be a double assignment instead of a triple assignment, like so:
x % 2 == 0
Remember to declare your variables too, so obviously that line couldn't be written standalone. :-) Usually used as an if
statement. Hope this helps.
array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
array.each { |x| puts x if x % 2 == 0 }
ruby :D
2 4 6 8 10
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