jQuery pitfalls to avoid [closed]

Answer 1

Use strings accumulator-style

Using + operator a new string is created in memory and the concatenated value is assigned to it. Only after this the result is assigned to a variable. To avoid the intermediate variable for concatenation result, you can directly assign the result using += operator. Slow:

a += 'x' + 'y';

Faster:

a += 'x';
a += 'y';

Primitive operations can be faster than function calls

Consider using alternative primitive operation over function calls in performance critical loops and functions. Slow:

var min = Math.min(a, b);
arr.push(val);

Faster:

var min = a < b ? a : b;
arr[arr.length] = val;

Read More at JavaScript Performance Best Practices