我正在创建一个react / redux应用程序来为角色扮演游戏制作角色,我希望能够在玩家状态下添加和删除技能。
我目前正在删除技能的方式如下:
const initState = {
activeSkills: {},
knowledgeSkills: {},
skillPointsSpent: 0
}
const skillReducer = (state=initState, action) => {
var {category, name} = action.parameter
const actionsToTake = {
...//other actions
DECREMENT_SKILL: () => {
var newState;
if(state[category][name].rating === 1) {
newState = Object.assign(
{},
state,
{
skillPointsSpent: state.skillPointsSpent - 1
}
);
delete newState[category][name];
}
return newState
},
...//other actions
}
return (actionsToTake[action.type] || actionsToTake.DEFAULT)();
}
我减少的状态应该看起来像这样,我试图删除射箭。因此,类别将为activeSkills
,名称将为Archery
state = {
activeSkills: {
Archery: {rating: 1, spec: 'Bow'}
},
knowledgeSkills: {},
skillPointsSpent: 1
}
这显然是错误的做法,因为它改变了我以前的状态。那么从状态对象中删除属性的不可变方法是什么?
答案 0 :(得分:0)
修改强>
就像链接到@flup链接的更新一样,处理此问题的更好方法是使用一些对象进行解构。
if(state[category][name].rating === 1) {
const { [name]: discard, ...newCategory } = state[category];
newState = {
...state,
[category]: {
...newCategory
},
skillPointsSpent: state.skillPointsSpent - 1
}
}
<强>原始强>
就像答案@flup linked to一样,我需要做的就是复制更深层次的嵌套对象,然后我可以删除属性而不会改变以前的状态。
if(state[category][name].rating === 1) {
newState = Object.assign(
{},
state,
{
[category] : Object.assign(
{},
state[category]
),
skillPointsSpent: state.skillPointsSpent - 1
}
);
delete newState[category][name];
}