Question

我有以下对象数组：

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> 
UITableViewCell {

let cell = collectionView.dequeueReusableCell(withReuseIdentifier:     
reuseIdentifier, for: indexPathOfCollectionView as IndexPath) as!   
MyCustomCollectionViewCell

if(tableView == cell.graphTableView){

let cell:CustomGraphTableViewCell =   
tableView.dequeueReusableCell(withIdentifier: "CustomGraphTableViewCell") as!    
CustomGraphTableViewCell

return cell
    }
    else
    {
        let cell:MyCustomTableViewCell = 
 tableView.dequeueReusableCell(withIdentifier: "MyCustomTableViewCell") as!   
 MyCustomTableViewCell
        cell.nameLabel.text = namesArray[indexPath.row]
        return cell

    }
}

我想过滤中等为True的此列表。我目前有这个设置。

var sizeList = [
    { id: 1, title:"Test1",
        type:[{name:"Big", present:false}, {name:"Small", present:true}, {name:"Medium", present:false}]
    },

    { id: 2,title:"Test2",
        type:[{name:"Big", present:false}, {name:"Small", present:true}, {name:"Medium", present:false}]
    },
    { id: 3,title:"Test3",
        type:[{name:"Big", present:false}, {name:"Small", present:true}, {name:"Medium", present:true}]
    }
  ]

这会不断返回一个空数组。我也试过这个：

var specificSizes = _.filter(sizeList.type, { 'name': 'Medium', 'present': true })

Answer 1

使用lodash，您可以将条件包装在与测试相同的结构中，作为原始对象。

_.filter(sizeList, { type: [{ name: 'Medium', present: true }] })

var sizeList = [{ id: 1, title: "Test1", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: false }] }, { id: 2, title: "Test2", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: false }] }, { id: 3, title: "Test3", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: true }] }],      
    result = _.filter(sizeList, { type: [{ name: 'Medium', present: true }] });

console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.15.0/lodash.min.js"></script>

在普通的Javascript中，您可以使用Array#filter作为外部数组，如果满足一个条件，请与Array#some核对。

var sizeList = [{ id: 1, title: "Test1", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: false }] }, { id: 2, title: "Test2", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: false }] }, { id: 3, title: "Test3", type: [{ name: "Big", present: false }, { name: "Small", present: true }, { name: "Medium", present: true }] }],      
    result = sizeList.filter(function (a) {
        return a.type.some(function (b) {
            return b.name === 'Medium' && b.present;
        });
    });
  
console.log(result);

.as-console-wrapper { max-height: 100% !important; top: 0; }

使用Lodash / Javascript过滤嵌套数组

1 个答案: