初探lodash

[youngwind]

目录

1. array
2. chain

Array

1.1 _.chunk(array, [size=1])平均分配数组到一个新的数组中

console.log(_.chunk(['a', 'b', 'c', 'd', 'e'], 1));
console.log(_.chunk(['a', 'b', 'c', 'd', 'e'], 2));
console.log(_.chunk(['a', 'b', 'c', 'd', 'e'], 3));
console.log(_.chunk(['a', 'b', 'c', 'd', 'e'], 4));
============================
[ [ 'a' ], [ 'b' ], [ 'c' ], [ 'd' ], [ 'e' ] ]
[ [ 'a', 'b' ], [ 'c', 'd' ], [ 'e' ] ]
[ [ 'a', 'b', 'c' ], [ 'd', 'e' ] ]
[ [ 'a', 'b', 'c', 'd' ], [ 'e' ] ]

1.2 _.compact(array) 数组去除null、0、false、“”、undefined、NaN项

console.log(_.compact([0,1,'',2,NaN,false,undefined,null,'3']))
=================================
[ 1, 2, '3' ]

1.3. _.difference(array,[values]) 差异对比，返回array中不存在[values]中的值

console.log(_.difference([1,2,3,4,5,6],[4,2]));
console.log(_.difference([1,2,3,4,5,6],[4,6,7]));
console.log(_.difference([1,2,3,4,5,6],[1,2,3]));
=============================================
[ 1, 3, 5, 6 ]
[ 1, 2, 3, 5 ]
[ 4, 5, 6 ]

1.4. _.drop(array,[n=1]) 从数组头删除n个元素，相当于unshift方法

_.drop([1,2,3])     => [2,3]
_.drop([1,2,3],2)  => [3]
_.drop([1,2,3],5)  => []

1.5 _.dropRight(array,[n=1]) 从数组尾删除n个元素，相当于pop方法

_.dropRight([1, 2, 3]);
// → [1, 2]

_.dropRight([1, 2, 3], 2);
// → [1]

_.dropRight([1, 2, 3], 5);
// → []

_.dropRight([1, 2, 3], 0);
// → [1, 2, 3]

1.6 _.dropRightWhile
1.7 _.ropWhile

1.8 _.fill(array, value, [start=0], [end=array.length]) 从array[start]到array[end]替换为value，不包括array[end]

var array = [1, 2, 3];

_.fill(array, 'a');
console.log(array);
// → ['a', 'a', 'a']

_.fill(Array(3), 2);
// → [2, 2, 2]

_.fill([4, 6, 8], '*', 1, 2);
// → [4, '*', 8]