I have a component that render data from a store in vuex
the component has a computed status when a search query has been written it will filter that store state which is kommunhanteringItems to search for a customer and here i have a problem which is the computed status will mutate the state in the store which i do not want it to do that.
State in the store which is this.$store.state.todos.kommunhanteringItems:
kommunhanteringItems: [
{
gId: 1,
gtitle: 'Group1',
items: [
{cid: 1, customer: 'Vicotria Nils'},
{cid: 2, customer: 'Mona Andersson'}
]
},
{
gId: 2,
gtitle: 'Group2',
items: [
{cid: 3, customer: 'Jacob Ström'},
{cid: 4, customer: 'Magdalin eriksson'}
]
}
]
Component computed:
SearchInTables() {
let k = this.$store.state.todos.kommunhanteringItems
if (this.SearchQuery != '') {
let SearchFilter = []
let self = this
k.forEach(function (x) {
let items = x.items
let filter = items.filter((item) => {
return item.customer.toUpperCase().includes(self.SearchQuery.toUpperCase())
})
x.items = filter
SearchFilter.push(x)
})
return SearchFilter
} else {
return k
}
},
The problem is that you are writing to x which is an object in an array in the store, when you do x.items = filter.
To avoid this, you need to create a copy of x, and replace items. See below for an example of doing this with Object.assign
SearchInTables() {
let k = this.$store.state.todos.kommunhanteringItems
if (this.SearchQuery != '') {
let SearchFilter = []
let self = this
k.forEach(function (x) {
let filter = x.items.filter((item) => {
return item.customer.toUpperCase().includes(self.SearchQuery.toUpperCase())
})
SearchFilter.push(Object.assign({}, x, { items: filter })
})
return SearchFilter
} else {
return k
}
}
Related
I need to sort array of objects by 2 conditions
sort by value
if names are the same show them next to each other in value order
Example example: https://codesandbox.io/s/relaxed-dhawan-sfryng?file=/src/index.js
I provide a solution for it,it's a bit complexed,you can read the comment I have added
const array = [
{
name: "John",
value: 5
},
{
name: "David",
value: 6
},
{
name: "John",
value: 2
},
{
name: "Michael",
value: 4
}
];
const customSort = (data) => {
// create a new array to make elements have same name together
let newArray = data.reduce((a,v) => {
let obj = a.find(e => e.name === v.name)
if(obj){
obj.datas.push(v)
}else{
a.push({'name':v.name,'datas':[v]})
}
return a
},[])
// sort data in the new array by value
newArray.forEach(e => {
e.datas.sort((a,b) => a.value - b.value)
})
// create a value object with boolean value to avoid add duplicate element
let values = data.reduce((a,v) => {
a[v.value] = false
return a
},{})
let keys = Object.keys(values)
let result = []
for(k of keys){
// if the value has iterated,then skip it
if(values[k]){
continue
}
// find data by value
let arr = newArray.filter(e1 => e1.datas.some(e2 => e2.value == k)).flatMap(e => e.datas)
result.push(...arr)
// mark the value already added
arr.forEach(e => {
values[e.value] = true
})
}
return result
}
console.log(customSort(array))
Hope it helps:
const arr = [
{
name: "John",
value: 5
},
{
name: "David",
value: 6
},
{
name: "John",
value: 2
},
{
name: "Michael",
value: 4
}
];
const groupByItems = [];
// Get index of the item based on name in groupByItems array
const getIndex = (name) => {
let index = -1;
groupByItems.forEach((groupByItem, _index) => {
if(groupByItem.name === name) {
index = _index;
}
});
return index;
}
// Group items by their name
const groupByName = () => {
arr.forEach((item) => {
const name = item.name;
const value = item.value;
let index = getIndex(name);
//Means that the [name] has not added before, so we should add it
if(index === -1) {
groupByItems.push({
name: name,
// Hold all values of the [name]
values: [],
// Hold minValue to sort groupByItems by that
minValue: Infinity
});
index = groupByItems.length - 1;
}
// Add current value to the list of values
groupByItems[index].values.push(value);
// Update minValue
if(groupByItems[index].minValue > value) {
groupByItems[index].minValue = value;
}
});
}
groupByName();
//Sort by minValue and then return final objects
const result = groupByItems.sort((a, b) => a.minValue - b.minValue).flatMap((item) => (
item.values.sort((firstValue, secondValue) => firstValue - secondValue).map((value) => {
return {
name: item.name,
value: value
}
})
));
console.log(result);
I have this kind of schema:
const schema = {
actions: {
ident: {
action: (v) => v,
path: 'some.path.key',
},
mul: {
action: (v) => v * 2,
path: 'some.other.path.key',
},
},
};
And a helper function, that takes object with keys present in schema actions, e.g:
const obj = {
ident: 1,
mul: 2,
}
const res = helper(schema, obj);
/* res */
{
some: {
path: {
key: 1,
},
other: {
path: {
key: 4,
}
}
},
}
And construct a new object with a function applied to the value.
Sometimes i need a behavior when both keys present in source object, e.g:
const schema2 = {
actions: {
ident: {
action: (v) => v,
path: 'some.path.key',
},
mul: {
action: (v) => v * 2,
path: 'some.other.path.key',
},
'mul:ident': {
action: (v1, v2) => v1/v2,
path: 'key',
}
},
};
In case like this, i need the result object to be:
const obj = {
ident: 1,
mul: 2,
}
const res = helper(schema, obj);
/* res */
{
key: 2 // 2/1 == 2
}
How can i implement such conditional logic in a good way?
I'd traverse your actions backwards, then delete the keys from the input, and skip the action if the keys are missing:
const input = { ...obj };
const output = {};
// you might want to sort the keys in the desired order first (e.g. by the number of parameters)
for(const [key, { action, path }] of Object.entries(schema.actions).reverse()) {
const keys = key.split(".");
// If one ov the values is missing, another action already consumed it
if(keys.some(key => !(key in input))
continue;
// consume all keys into values
const values = keys.map(key => {
const value = input[key];
delete input[key];
});
// TODO: assign path to output correctly
output[path] = action(...values);
}
I'm trying to figure out how to add new items into array instead of overriding the current value with the new value. I'm using .push() which should add the item every time it maps through the array. Any Ideas?
const searchChips = [
{value: "string"}, {value: "test"}
];
const query = {
bool: {
filter: []
}
};
const searchQuery = {
query_string: {
query: ""
}
};
searchChips.map(chip => {
console.log(chip);
const key = "query";
searchQuery.query_string[key] = chip.value;
query.bool.filter.push(searchQuery);
});
console.log(query);
You are inserting the same query since you are dealing with the same exact reference to the searchQuery. Instead of this try having it as a function which returns an object:
const searchChips = [{
value: "string"
}, {
value: "test"
}];
const query = {
bool: {
filter: []
}
};
let sq = (query) => ({
query_string: {query}
});
searchChips.map(chip => query.bool.filter.push(sq(chip.value)));
console.log(query);
This will return to you the 2 filters each with different values for query_string since now the function will return an entirely new object instead of you dealing with the same reference.
The problem seems to be that you are pushing into query.bool.filter outside the .map() function. Try this.
const searchChips = [{ value: "string" }, { value: "test" }];
const query = {
bool: {
filter: []
}
};
searchChips.forEach(chip => {
const key = "query";
const searchQuery = {
query_string: {
query: ""
}
};
searchQuery.query_string[key] = chip.value;
query.bool.filter.push(searchQuery);
});
console.log(JSON.stringify(query));
This answer is already close, and there are some answers how to get unique values in an array (remove duplicates,)though I can't make it work for the case where it is about an array of objects, and the property that should be filtered is an array. Sorry, I am a JS newbie. Thanks for the help.
I have an array of objects like this
const posts = [
post1: {
id: 1,
title: 'One',
tags: ['tagA', 'tagB']
},
post2: {
id: 2,
title: 'Two',
tags: ['tagB', 'tagC']
},
post3: {
id: 3,
title: 'Three',
tags: ['tagB', tagC, tagD]
]
What I would need is an array of all unique tags ... in the case above with an expected output like this:
// [tagA, tagB, tagC, tagD]
EDIT / UPDATE
The key in the array of objects is used to manage the state of the react component... e.g.
constructor(props) {
super(props);
this.state = {
posts: []
};
}
...
updatePost = (key, updatedPost) => {
//1. Take copy of the current this.state.
const posts = {...this.state.texts};
//2. Update that state
posts[key] = updatedPost;
//3. Set that to state
const options = { encrypt: false }
putFile(postsFileName, JSON.stringify(posts), options)
.then(() => {
this.setState({
posts: posts
})
})
};
Assuming that the input is on [ {} , {} ] format:
You can use concat and map to flatten your array. Use new Set to get the unique values.
const posts = [{"id":1,"title":"One","tags":["tagA","tagB"]},{"id":2,"title":"Two","tags":["tagB","tagC"]},{"id":3,"title":"Three","tags":["tagB","tagC","tagD"]}];
var result = [...new Set([].concat(...posts.map(o => o.tags)))];
console.log(result);
If the variable is an object ( {a:{} , b:{} } ) , you can use Object.values to convert the object into an array.
const posts = {"post1":{"id":1,"title":"One","tags":["tagA","tagB"]},"post2":{"id":2,"title":"Two","tags":["tagB","tagC"]},"post3":{"id":3,"title":"Three","tags":["tagB","tagC","tagD"]}}
var result = [...new Set([].concat(...Object.values(posts).map(o => o.tags)))];
console.log(result);
You can reduce your posts and iterate over the tags and push those to the result that you haven't encountered already:
const posts = [
{
id: 1,
title: "One",
tags: ["tagA", "tagB"]
},
{
id: 2,
title: "Two",
tags: ["tagB", "tagC"]
},
{
id: 3,
title: "Three",
tags: ["tagB", "tagC", "tagD"]
}
];
const uniqueTags = posts.reduce((result, post) => {
post.tags.forEach(tag => {
if (!result.includes(tag)) {
result.push(tag);
}
});
return result;
}, []);
console.log(uniqueTags);
This is assuming you know that the array key is always 'tags'.
let filter = {};
let result = [];
posts.forEach(post => {
const tags = post['tags'];
tags.forEach(tag => {
if (!filter.hasOwnProperty(tag)) {
result.push(tag);
filter[tag] = true;
}
});
});
with jquery you can do something similar to this (not Tested):
var results = [];
$.each(myObject, function(key,valueObj){
var check.isArray(obj);
if(check){
alert(key + "/" + valueObj );
/*replace repeat*/
var sorted_check = check.slice().sort(); // You can define the comparing function here.
// JS by default uses a crappy string compare.
// (we use slice to clone the array so the
// original array won't be modified)
for (var i = 0; i < sorted_check.length - 1; i++) {
if (sorted_check[i + 1] == sorted_check[i]) {
results.push(sorted_check[i]);
}
}
}
});
and a good way with indexof:
Array.prototype.unique = function() {
var a = [];
for ( i = 0; i < this.length; i++ ) {
var current = this[i];
if (a.indexOf(current) < 0) a.push(current);
}
this.length = 0;
for ( i = 0; i < a.length; i++ ) {
this.push( a[i] );
}
return this;
}
Array.prototype.unique = function() {
var a = [];
for ( i = 0; i < this.length; i++ ) {
var current = this[i];
if (a.indexOf(current) < 0) a.push(current);
}
return a;
}
And Follow UP:
Array.prototype.unique = function(mutate) {
var unique = this.reduce(function(accum, current) {
if (accum.indexOf(current) < 0) {
accum.push(current);
}
return accum;
}, []);
if (mutate) {
this.length = 0;
for (let i = 0; i < unique.length; ++i) {
this.push(unique[i]);
}
return this;
}
return unique;
}
If you want to use a functional library like Ramda.js you can do this:
const posts = [
{
id: 1,
title: 'One',
tags: ['tagA', 'tagB'],
},
{
id: 2,
title: 'Two',
tags: ['tagB', 'tagC'],
},
{
id: 3,
title: 'Three',
tags: ['tagB', 'tagC', 'tagD'],
},
];
var unique = R.uniq(R.flatten(R.map(R.prop('tags'), posts)))
console.log(unique)
<script src="https://cdnjs.cloudflare.com/ajax/libs/ramda/0.25.0/ramda.min.js"></script>
The relevant Redux state consists of an array of objects representing layers.
Example:
let state = [
{ id: 1 }, { id: 2 }, { id: 3 }
]
I have a Redux action called moveLayerIndex:
actions.js
export const moveLayerIndex = (id, destinationIndex) => ({
type: MOVE_LAYER_INDEX,
id,
destinationIndex
})
I would like the reducer to handle the action by swapping the position of the elements in the array.
reducers/layers.js
const layers = (state=[], action) => {
switch(action.type) {
case 'MOVE_LAYER_INDEX':
/* What should I put here to make the below test pass */
default:
return state
}
}
The test verifies that a the Redux reducer swaps an array's elements in immutable fashion.
Deep-freeze is used to check the initial state is not mutated in any way.
How do I make this test pass?
test/reducers/index.js
import { expect } from 'chai'
import deepFreeze from'deep-freeze'
const id=1
const destinationIndex=1
it('move position of layer', () => {
const action = actions.moveLayerIndex(id, destinationIndex)
const initialState = [
{
id: 1
},
{
id: 2
},
{
id: 3
}
]
const expectedState = [
{
id: 2
},
{
id: 1
},
{
id: 3
}
]
deepFreeze(initialState)
expect(layers(initialState, action)).to.eql(expectedState)
})
One of the key ideas of immutable updates is that while you should never directly modify the original items, it's okay to make a copy and mutate the copy before returning it.
With that in mind, this function should do what you want:
function immutablySwapItems(items, firstIndex, secondIndex) {
// Constant reference - we can still modify the array itself
const results= items.slice();
const firstItem = items[firstIndex];
results[firstIndex] = items[secondIndex];
results[secondIndex] = firstItem;
return results;
}
I wrote a section for the Redux docs called Structuring Reducers - Immutable Update Patterns which gives examples of some related ways to update data.
You could use map function to make a swap:
function immutablySwapItems(items, firstIndex, secondIndex) {
return items.map(function(element, index) {
if (index === firstIndex) return items[secondIndex];
else if (index === secondIndex) return items[firstIndex];
else return element;
}
}
In ES2015 style:
const immutablySwapItems = (items, firstIndex, secondIndex) =>
items.map(
(element, index) =>
index === firstIndex
? items[secondIndex]
: index === secondIndex
? items[firstIndex]
: element
)
There is nothing wrong with the other two answers, but I think there is even a simpler way to do it with ES6.
const state = [{
id: 1
}, {
id: 2
}, {
id: 3
}];
const immutableSwap = (items, firstIndex, secondIndex) => {
const result = [...items];
[result[firstIndex], result[secondIndex]] = [result[secondIndex], result[firstIndex]];
return result;
}
const swapped = immutableSwap(state, 2, 0);
console.log("Swapped:", swapped);
console.log("Original:", state);