用req.query填充数组

Question

I want to fill an array with req.params, so i can edit my code easily right now the code is like this .

let test = [req.query.t0,req.query.t1,req.query.t2,req.query.t3,req.query.t4,req.query.t5,req.query.t6,req.query.t7,req.query.t8,req.query.t9,req.query.t10,req.query.t11]

Is there a way to fill easily my array with a loop or a fill map ?

something like this.

let init = 0;
let end = 19;
let test = Array(req.query.init-req.query.end+1)
.fill()
.map(() => init++);

Answer 1

If you can use Object.values :

 var req = { query: { t0: 't0', t1: 't1', t2: 't2' }}; var params = Object.values(req.query); console.log(params); 

Or with Object.keys if you cannot:

 var req = { query: { t0: 't0', t1: 't1', t2: 't2' }}; var params = Object.keys(req.query).map(key => req.query[key]); console.log(params); 

In case you want to retrieve a limited number of parameters, you can add array.prototype.filter :

 var req = { query: { t0: 't0', t1: 't1', t2: 't2', t3: 't3', t4: 't4' }}; var nbParams = 3; var params = Object.keys(req.query).filter((key, i) => i < nbParams).map(key => req.query[key]); console.log(params); 

Answer 2

Actually your API should take an array instead, like:

yourapi?t=one&t=two&t=three

And you can get the array like this:

 req.query.t // ["one", "two", "three"]

More info

Answer 3

Assuming rep.query properties reliably start with t and end with numbers:

 function fillArrayFromReq(query, start, end) { return Array.from({ length: end - start }, (_, i) => { const propNum = i + start; return query[`t${propNum}`]; }); } const query = { t0: 0, t1: 1, t2: 2, t3: 3, t4: 4, t5: 5, t6: 6, t7: 7, t8: 8, t9: 9, } console.log(fillArrayFromReq(query, 4, 7)); 

Object.values isn't entirely reliable because you can't always count on properties to have been added in order.

Answer 4

Let me just aggregate and expand on the other nice answers. To get all the params values:

 const query = { a: 'a val', num: 4, t0: 't0 val', t1: 't1 val' }; let array = Object.values(query); // -> [ val1, val2, val3 ...] console.log(array); // or with [{key: value}] pairs array = Object.keys(query) .map(key => ({[key]: query[key]})); // -> [ { param: val1 }, { anotherParam: val2 }, ... ] console.log(array); 

But you had a different example, your params were starting with 't' followed by number:

 const query = { a: 'a val', num: 4, t0: 't0 val', t1: 't1 val' }; const array = Object.keys(query) .filter(key => /^t\\d+$/.test(key)) // only take params whose keys start with a letter t, followed only by a number. .map(key => query[key]); console.log(array); 

Finally, you also had a limit, from t0 to t19:

 const query = { a: 'a val', num: 4, t0: 't0 val', t1: 't1 val', t19: 't19 val', t20: 't20 val' }; const array = Object.keys(query) .filter(key => /^t([0-9]|[01][0-9])$/.test(key)) // match keys starting with at, followed by a number between 0 and 19 .map(key => query[key]); // or .map(key => ({[key]: query[key]})) console.log(array); 

Or a bit more generic, take all t<number> params , but slice between init and end :

 const query = { a: 'a', num: 4, t0: 't0', t1: 't1' }; let init = 0; let end = 19; const array = Object.keys(query) .filter(key => /^t\\d+$/.test(key)) .map(key => query[key]) // or .map(key => ({[key]: query[key]})) .slice(init, end); console.log(array); 

This doesn't check that the order is correct, eg if you skip t2, we go from t0 to t20, so once more:

 const query = { a: 'a', num: 4, t0: 't0', t1: 't1' }; let init = 0; let end = 19; const array = Object.keys(query) .filter(key => /^t\\d+$/.test(key)) .filter(key => { let num = parseInt(key.substring(1), 10); return num >= init && num <= end; }) .map(key => query[key]); // or .map(key => ({[key]: query[key]})); console.log(array);