[英]ImmutableJS - update value in a List
I have a Map like this (in ImmutableJS): 我有这样的地图(在ImmutableJS中):
{arrayOfValues: [
{one: {inside: 'first in array'}},
{one: {inside: 'second in array'}}
]}
And I want to update the value "inside" in the second entry in the "arrayOfValues" array. 我想更新“arrayOfValues”数组中第二个条目中的“inside”值。 How can I do it? 我该怎么做? This is what I have now and it says "Uncaught Error: invalid keyPath" 这就是我现在所说的“Uncaught Error:invalid keyPath”
theMap.update('arrayOfValues',(list)=>{
return list.setIn([1,'one','inside'],'updated value');
})
I also tried directly this and it didn't work: 我也直接尝试了这个并没有用:
theMap.setIn(['arrayOfValues',1,'one','inside'],'updated value');
After several hours of looking for the solution, I appreciate any help. 经过几个小时的寻找解决方案,我感谢任何帮助。 Thank you. 谢谢。
What you are doing is correct (see this JSBin ). 你在做什么是正确的(参见这个JSBin )。
const orig = Immutable.fromJS({
arrayOfValues: [
{ one: { inside: 'first in array' } },
{ one: { inside: 'second in array' } },
]
});
const updated = orig.setIn(['arrayOfValues', 1, 'one', 'inside'], 'updated value');
console.log(updated.toJS());
// {
// arrayOfValues: [
// { one: { inside: 'first in array' } },
// { one: { inside: 'second in array' } },
// ]
// }
When you call orig.setIn()
, it doesn't modify orig
directly. 当您调用orig.setIn()
,它不会直接修改orig
。 That's the whole purpose of this Immutable
library. 这就是这个Immutable
库的全部目的。 It doesn't mutate the existing data but creates a new one from the existing one. 它不会改变现有数据,而是从现有数据中创建一个新数据。
Your setIn
example works as you should see in this plunkr: http://plnkr.co/edit/1uXTWtKlykeuU6vB3xVO?p=preview 您的setIn
示例的工作原理与您在此plunkr中看到的一样: http ://plnkr.co/edit/1uXTWtKlykeuU6vB3xVO?p = preview
Perhaps you are assuming the value of theMap
will be changed as a result of the setIn
? 也许你正在承担的价值theMap
将被改变为的结果setIn
?
As these structures are immutable, you must capture the modified value in a new variable as var theMap2 = theMap.setIn(['arrayOfValues',1,'one','inside'],'updated value');
由于这些结构是不可变的,因此必须在新变量中捕获修改后的值,如var theMap2 = theMap.setIn(['arrayOfValues',1,'one','inside'],'updated value');
activePane is the index of Object in Array(List) that I had to modify activePane是我必须修改的Array(List)中Object的索引
case CHANGE_SERVICE:
var obj = {
title: '1212121 Tab',
service: '',
tagName: '',
preDefinedApi: '',
methodType: '',
url: '',
urlParams: [{
label: '',
name: '',
value: '',
}],
headers: [{
label: '',
name: '',
value: '',
}],
};
var activePane = state.get('activePane');
var panes = state.setIn(['panes', activePane, 'service'], action.val);
return state.setIn(['panes', activePane, 'service'], action.val);
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