JavaScript iterative methods, merging methods

1. Iterative Methods

　　every (FN): runs the given function for each item in the array, and returns True if the function returns true for each item.

　　Some (FN): runs the given function for each item in the array, and returns True if the function returns true for either item.

　Filter (FN): runs the given function for each item in the array, and returns a type that matches a certain condition.

　　ForEach (FN): runs the given function for each item in the array, with no return value.

　　Map (FN): each item in the array runs the given function, returning an array that consists of the results of each function call.

2. Merge method

ECMAScript5 added 2 methods for merging arrays:reduce () and reduceright ().

　　reduce (): traverse through to the end one at a start of the first entry.

reduceright (): iterates to the first item of the array, starting with the last item in the array.

    var values = [1, 2, 3, 4, 5];    var sum = values.reduce (function (prev, cur, index, array) {        return prev + cur;    });    alert (sum);    As a result, it's just the opposite.    var sum2=values.reduceright (function (prev,cur,index,array) {        return prev+cur;    });    alert (SUM2);

　　

JavaScript iterative methods, merging methods