我是新來的反應和redux。我有一個對象是子對象,其中包含數組替換深的子對象,同時保持狀態在React中不可變
const initialState = {
sum: 0,
denomGroups: [
{
coins: [
{ name: 'Penny', namePlural: 'Pennies', label: '1¢', value: .01, sum: 0 },
{ name: 'Nickel', namePlural: 'Nickels', label: '5¢', value: .05, sum: 0 },
{ name: 'Dime', namePlural: 'Dimes', label: '10¢', value: .10, sum: 0 },
{ name: 'Quarter', namePlural: 'Quarters', label: '25¢', value: .25, sum: 0 }
]
},
{
bills: [
{ name: 'Dollar', namePlural: 'Dollars', label: '$1', value: 1, sum: 0 },
{ name: 'Five', namePlural: 'Fives', label: '$5', value: 5, sum: 0 },
{ name: 'Ten', namePlural: 'Tens', label: '$10', value: 10, sum: 0 },
{ name: 'Twenty', namePlural: 'Twentys', label: '$20', value: 20, sum: 0 },
{ name: 'Fifty', namePlural: 'Fiftys', label: '$50', value: 50, sum: 0 },
{ name: 'Hundred', namePlural: 'Hundreds', label: '$100', value: 100, sum: 0 }
]
}
]
};
數組我有被傳遞一個值,面額
export function increaseSum(value, denom) {
return { type: types.ADD_TO_SUM, value: value, denom: denom }
}
裏面我減速的我寫了一個名稱的行動輔助類,以查明該教派是對象中:
function findDenomination(denoms, action) {
let denomMap = {},
currentDenom = {};
for (let i = 0; denoms.length >= i + 1; i++) {
let denomGroup = denoms[Object.keys(denoms)[i]];
for (var key in denomGroup) {
if (!currentDenom.length) {
currentDenom = denomGroup[key].filter(x => x.name === action.denom);
if (currentDenom.length > 0) {
denomMap.group = i;
denomMap.key = key;
denomMap.index = denomGroup[key].findIndex(x => x.name === action.denom);
}
}
}
if (currentDenom.length > 0) {
break;
}
}
return denomMap;
}
和減速器本身我使用Object.assign
使denomGroup的深層副本以我認爲保持不變的方式。
function countableItems(state = initialState, action) {
switch (action.type) {
case types.ADD_TO_SUM:
let denomMap = findDenomination(state.denomGroups, action);
state.denomGroups = Object.assign({}, state.denomGroups, state.denomGroups[denomMap.group][denomMap.key][denomMap.index].sum = parseFloat(action.value));
return state;
default:
return state;
}
}
是明確告訴任何人這是爲什麼越來越有錯誤標記:A state mutation was detected inside a dispatch
你修改狀態:'state.denomGroups = ...'' – Li357
返回Object.assign({},狀態,state.denomGroups [denomMap.group] [ denomMap.key] [denomMap.index] .sum = parseFloat(action.value));'仍然拋出突變錯誤 –
'state.denomGroups [denomMap.group] [denomMap.key] [denomMap.ind ex] .sum = parseFloat(action.value)'仍然是一個狀態變異 – Li357