I have a javascript array which get created dynamically in this format.
[{prdName: "Testing2"},
{prdName: "Testing2,Testing3"},
{markets: "Testing5"},
{markets: "Testing5,Testing6"}]
I want to remove the duplicate key in the above array map and convert it into this format.
[ {prdName: "Testing2,Testing3"},
{markets: "Testing5,Testing6"} ]
Could you let me know how to achieve the same. I am working on a reactjs application.
With ES6, you could use Map with Set for unique items.
var array = [{ prdName: "Testing2" }, { prdName: "Testing2,Testing3" }, { markets: "Testing5" }, { markets: "Testing5,Testing6" }],
map = new Map,
result;
array.forEach(o => Object.keys(o).forEach(k => {
if (!map.has(k)) {
map.set(k, new Set);
}
o[k].split(',').forEach(s => map.get(k).add(s));
}));
result = [...map].map(([k, s]) => ({ [k]: [...s].join() }));
console.log(result);.as-console-wrapper { max-height: 100% !important; top: 0; }I'm assuming that you want to preserve all of the non-duplicate comma-delimited entries, not just throw away all but the last group as in the other answers. (So, for example, if the input were [{foo: "x"}, {foo:"x,y"}, {foo:"z"}] the output should be [{foo: "x,y,z"}], not [{foo:"z"}].)
var rearrange = function(input) {
var tmp = {}; // track keys and values as we find them
for (obj of input) {
var key = Object.keys(obj)[0]; // each input has one key
tmp[key] = tmp[key] || {}; // initialize an empty object at that key in tmp if necessary
var vals = obj[key].split(",");
for (v of vals) {
tmp[key][v.trim()] = 1; // keep each of the (trimmed) comma-delimited values, implicitly dropping duplicates
}
}
// now convert the tmp object into an array:
var output = [];
for (k of Object.keys(tmp)) {
var x = {};
x[k] = Object.keys(tmp[k]).join(","); // merge the values back into a comma-separated string
output.push(x);
}
return output;
}
console.log(rearrange([
{prdName: "Testing2"},
{prdName: "Testing2,Testing3"},
{markets: "Testing5"},
{markets: "Testing5,Testing6"}
]));
console.log(rearrange([
{foo: "x"},
{foo: "x,y"},
{foo: "z"},
{bar: "x,y,z"}
]));If, however, all you need is the last instance of each key, this is pretty close to a one-liner; just use Object.assign to merge the objects:
var rearrange = function(input) {
var merged = Object.assign({},...input); // merges all input keys, overwriting early values with later ones
// convert to array (if necessary. the "merged" object might be easier to work with...):
var output=[];
for (k of Object.keys(merged)) {
var x = {};
x[k] = merged[k];
output.push(x)
}
return output;
}
console.log(rearrange([
{prdName: "Testing2"},
{prdName: "Testing2,Testing3"},
{markets: "Testing5"},
{markets: "Testing5,Testing6"}
]));
console.log(rearrange([{foo: "x"}, {foo:"x,y"}, {foo:"z"}]));var lists =[{prdName: "Testing2"},
{prdName: "Testing2,Testing3"},
{markets: "Testing5"},
{markets: "Testing5,Testing6"}]
var newLists =[]
var keys = []
lists.forEach(item=>{
var key = Object.keys(item)[0];
if(keys.indexOf(key) === -1){
// first time the key is processed; it is stored in newLists
keys.push(key);
newLists.push(item);
}
else {
// a duplicate key is found in the array
let remove;
let values;
newLists.forEach((item2,index) => {
if (Object.keys(item2)[0] === key) {
// use of a set to have a union of values already stored for the key and the new values found for the same key using spread operator
values = new Set([...item2[key].split(","),...item[key].split(",")]);
remove = index;
}
})
newLists.splice(remove, 1);
newLists.push({[key]: Array.from(values).toString()})
}
})
console.log(newLists);
format"; I could modify my post or even delete it since there are others answers. But I guess, the question would have been easier to understand, if the JSON you gave were more general
console.log('correct output') and saying "well you didn't say it wouldn't always be the exact same input..."
[{a:"Test1"}, {a:"Test2"}]the result must be[{a:"Test1,Test2"}]or it's enough to just get the latest ocurrence of "a" (resulting in[{a:"Test2"}])?