Immutable.js

Immutable.js它內部實現了一套完整的 Persistent Data Structure

 

fromJS()

---

將數組或者對象轉換爲Immutable

let map=Immutable.fromJS({
        a:1,
        b:2
    });
    let list=Immutable.fromJS([
        {
            a:1,
            b:2
        }
    ]);
    console.log(map);
    console.log(list);

 

is()

---

檢測是否相等，和Object.is()是有區別的

let map1=Immutable.Map({a:1});
    let map2=Immutable.Map({a:1});
    console.log(map1===map2);   //false
    console.log(Object.is(map1,map2));  //false
    console.log(Immutable.is(map1,map2));   //true

　　

List是個索引集合

---

 

List.isList() 判斷是否爲List集合

let list=Immutable.List([1,2,3]);
    console.log(Immutable.List.isList(list));   //true

List.of()建立一個集合

console.log(Immutable.List.of([1,2,3]));

List大小

let list=Immutable.List([1,2,3]);
    console.log(list.size); //3
    console.log(list.count());  //3

獲取List索引元素

console.log(list.get(0));
    console.log(list.get(-1));  //反向索引

更新

 let list=Immutable.List([0, 0, [1, 2]]);
    let list1=list.set(0,2);
    let list2=list.update(1,v=>2);

遍歷

let list=Immutable.List([0, 0, [1, 2]]);
    list.forEach((item,index,array)=>{
        console.log(item);
        console.log(index);
        console.log(array);
        return false;   //返回false跳出,true繼續
    });

查找

let list=Immutable.List([0,0, [1, 2]]);
    //返回一個匹配值
    console.log(list.find(x=>x===0));
    //返回匹配值的集合
    console.log(list.filter(x=>x===0));
    //返回不匹配值的集合
    console.log(list.filterNot(x=>x===0));

　　

Map

---

建立

let map=Immutable.Map({a:1,b:2});
    let map1=Immutable.fromJS({a:1,b:2});

判斷

let map=Immutable.Map({a:1,b:2});
    console.log(Immutable.Map.isMap(map));  //true

獲取

let map=Immutable.Map({a:1,b:2});
    let map1=Immutable.fromJS({a:{b:2},b:2});
    console.log(map.get('a'));  //1
    //獲取樹
    console.log(map1.getIn(['a','b'])); //2

更新

let map=Immutable.Map({a:1,b:2});
    let map1=map.set('a',2);
    let map2=map.update('a',value=>3);
    console.log(map1);
    console.log(map2);
    let map3=Immutable.fromJS({
        a:{
            b:1
        }
    });
    let map4=map3.updateIn(['a','b'],value=>2);
    console.log(map4.toJS());
    let map5=map3.setIn(['a','b'],5);
    console.log(map5.toJS());

合併

let map=Immutable.Map({a:1,b:2});
    let map3=Immutable.fromJS({
        a:{
            b:1
        }
    });
    let map4=map.merge(map3);
    console.log(map4.toJS());

判斷是否存在key

let map=Immutable.Map({a:1,b:2});
    console.log(map.has('a'))

查找

let map=Immutable.Map({a:1,b:2});
    let map1=map.filter(a=>a===1);
    let map2=map.find(a=>a===1);
    console.log(map1.toJS());
    console.log(map2);

遍歷

let map=Immutable.Map({a:1,b:2});
    map.forEach((value,key,object)=>{
        console.log(value);
        console.log(key);
        console.log(object);
    });