Array.Sort of JavaScript Learning notes

Arrayname.sort () Method:

The function is to implement sorting (by ASCII encoding or by number size), can be used without parameters or parameters, the default ascending order when no parameter. When you have a parameter that can be sorted in ascending or descending order, the parameter must be a method with a return value, and the method expression will exchange two number of digits if it is greater than 0 o'clock. That

Arrayname.sort (Expression {if (expression >0)   Exchange order; else if (expression <0)    does not perform an operation;    else//Expression =0  Select specific actions according to browser support;});

where the expression (= = method) will determine the sorting principle, specifically the instance is

Arrayname.sort (function(b) {    if(a>b)        return 1;     else if (a<b)         return -1;     Else// (a=b)         return 0;});   

will be sorted in ascending order, the corresponding way to achieve descending order is:

Arrayname.sort (function(b) {    if(a>b)        return -1;     Else if (a<b)         return 1;     Else // a===b        return 0;});

When the array content of the comparison is a number, the above expression can be simplified to:

// Ascending arrayname.sort (function(b) {    return A-b;}); // Descending arrayname.sort (function(A, b    ) {return b-a;});

In addition, the sort method, depending on the expression, also implements the ability to sort based on the content of the element, as described in Array.prototype.sort ().

Array.Sort of JavaScript Learning notes