salesforce 零基礎學習（六十三）Comparable實現Object列表資料的自訂排序

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項目中通常有些需求為需要將某個sObject的資料列表按照某種規則排序顯示到前台頁面上，但是list上面的sort遠遠滿足不了複雜的功能，此種情況需要自訂比較兩個object大小的方法，所以需要建立Compare相關的類實現Comparable介面。

 需求：實現Goods__c列表排序，GoodsBrand__c為華為的按照價格升序排序，GoodsBrand__c為聯想的按照價格降序排列。

 1 public without sharing class ComparedGoods implements Comparable{ 2     private Goods__c goods{get;set;} 3      4     private static final String GOODS_BRAND_HUAWEI = ‘華為‘; 5      6     private static final String GOODS_BRAND_LIANXIANG = ‘聯想‘; 7      8     public ComparedGoods(Goods__c obj) { 9         goods = obj;10     }11     12     public Integer compareTo(Object objectToCompareTo) {13             Goods__c comparedGoods = (Goods__c)objectToCompareTo;14             Integer comparedResult = 0;15             if(comparedGoods.GoodsBrand__c == GOODS_BRAND_HUAWEI) {16                 if(goods.GoodsPrice__c > comparedGoods.GoodsPrice__c) {17                     comparedResult = 1;18                 } else if(goods.GoodsPrice__c < comparedGoods.GoodsPrice__c) {19                     comparedResult = -1;20                 }21             } else if(comparedGoods.GoodsBrand__c == GOODS_BRAND_LIANXIANG) {22                 if(goods.GoodsPrice__c > comparedGoods.GoodsPrice__c) {23                     comparedResult = -1;24                 } else if(goods.GoodsPrice__c == comparedGoods.GoodsPrice__c) {25                     comparedResult = 0;26                 } 27                 else if(goods.GoodsPrice__c < comparedGoods.GoodsPrice__c) {28                     comparedResult = 1;29                 }30             }31             return comparedResult;32     }33 }

用法：

總結：針對object需要比較大小的時候，可以實現Comparable介面，在其compareTo方法中實現比較的邏輯即可。此篇有錯誤的地方歡迎指正，有問題歡迎留言。

salesforce 零基礎學習（六十三）Comparable實現Object列表資料的自訂排序