故事大綱

由於業務需求，我需要對物件陣列進行多個屬性的排序，於是我在Github找到好用的套件thenBy
它的使用方式很簡單，直接在sort函式中，呼叫套件中的firstBy函式，如果還有要針對其他函式進行排序，就再多叫幾個thenBy函式就好。

真心覺得對我幫忙很大，推薦給大家

使用方式如下

let data = [....];

data.sort(firstBy("id").thenBy((a,b)=>{ return a.length - b.length;}));

其他使用方式我就不多說，請自行到套件的github上查閱說明文件，連接放在參考文獻

 給我自己用的

/***

Copyright 2013 Teun Duynstee

Licensed under the Apache License, Version 2.0 (the "License");

you may not use this file except in compliance with the License.

You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software

distributed under the License is distributed on an "AS IS" BASIS,

WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

See the License for the specific language governing permissions and

limitations under the License.

*/

var firstBy = (function() {

function identity(v){return v;}

function ignoreCase(v){return typeof(v)==="string" ? v.toLowerCase() : v;}

function makeCompareFunction(f, opt){

opt = typeof(opt)==="object" ? opt : {direction:opt};

if(typeof(f)!="function"){

var prop = f;

// make unary function

f = function(v1){return !!v1[prop] ? v1[prop] : "";}

}

if(f.length === 1) {

// f is a unary function mapping a single item to its sort score

var uf = f;

var preprocess = opt.ignoreCase?ignoreCase:identity;

var cmp = opt.cmp || function(v1,v2) {return v1 < v2 ? -1 : v1 > v2 ? 1 : 0;}

f = function(v1,v2) {return cmp(preprocess(uf(v1)), preprocess(uf(v2)));}

}

const descTokens = {"-1":'', desc:''};

if(opt.direction in descTokens) return function(v1,v2){return -f(v1,v2)};

return f;

}

/* adds a secondary compare function to the target function (`this` context)

which is applied in case the first one returns 0 (equal)

returns a new compare function, which has a `thenBy` method as well */

function tb(func, opt) {

/* should get value false for the first call. This can be done by calling the

exported function, or the firstBy property on it (for es6 module compatibility)

*/

var x = (typeof(this) == "function" && !this.firstBy) ? this : false;

var y = makeCompareFunction(func, opt);

var f = x ? function(a, b) {

return x(a,b) || y(a,b);

}

: y;

f.thenBy = tb;

return f;

}

tb.firstBy = tb;

return tb;

})();

 參考文獻

Github - thenBy