CODEWITHSUNDEEP
javascriptarraysstring
Hugo LOPEZ
Hugo LOPEZ

Reputation: 615

Convert array of arrays to string?

Given an array of arrays with 2 vals such :

var arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];

I currently use this or variations of this :

var arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];

var arrayToString = function(array){ 
  var str;
  array.map(function(a) {
    var item = a[0]+":"+a[1];
    str = str? str+'; '+item : item;
    } 
  );
return str
}
var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

Or 

var arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];

var arrayToString = function(array){ 
  return str =  JSON.stringify(array).replace(/\"|\[\[|\]\]/g , "").replace(/\],\[/g , "; ").replace(/,/g , ":");
}
var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

Is there a slicker way to do obtain str= "G14:18; G16:17; G16:17; G13:17"

Upvotes: 2

Views: 7237

Answers (5)

Hugo LOPEZ
Hugo LOPEZ

Reputation: 615

Highly inspired by previous suggestions, yet shorter and more readable than others :

var arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];

var arrayToString = function(array){ 
  return array.join("; ").replace(/,/g,":")
}
console.log(arrayToString(arrayStd));

Upvotes: 1

Yogy Saini
Yogy Saini

Reputation: 32

let arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];
//"G14:18; G16:17; G16:17; G13:17"

let arrayNew = arrayStd.map((elem,i) => `${i!==0?'; 
':''}${elem[0]}:${elem[1]}`).join("");
console.log(arrayNew);

Upvotes: 0

Renzo Calla
Renzo Calla

Reputation: 7696

You can use map function, and join the resulting array.

let arrayStd = [["G14",18],["G16",17],["G16",17],["G13",17]];
//"G14:18; G16:17; G16:17; G13:17"

let arrayNew = arrayStd.map((elem,i) => `${i!==0?'; ':''}${elem[0]}:${elem[1]}`).join("");
console.log(arrayNew);

Upvotes: 0

user2437417
user2437417

Reputation:

Making incremental improvements to your code...

You should be using .forEach() instead of .map() since you're not returning anything.

var arrayStd = [
  ["G14", 18],
  ["G16", 17],
  ["G16", 17],
  ["G13", 17]
];

var arrayToString = function(array) {
  var str = "";
  array.forEach(function(a) {
    var item = a[0] + ":" + a[1];
    str = str ? str + '; ' + item : item;
  });
  return str
}
var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

However, .map() is actually useful here to map each inner array to a string, then take the new array of strings and join them.

var arrayStd = [
  ["G14", 18],
  ["G16", 17],
  ["G16", 17],
  ["G13", 17]
];

var arrayToString = function(array) {
  var str = array.map(function(a) {
    return a[0] + ":" + a[1];
  }).join("; ");

  return str
}
var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

You can also use .join() on the inner array, and can get rid of the str variable by returning the result immediately.

var arrayStd = [
  ["G14", 18],
  ["G16", 17],
  ["G16", 17],
  ["G13", 17]
];

var arrayToString = function(array) {
  return array.map(function(a) {
    return a.join(":");
  }).join("; ");
}
var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

Finally, in modern environments, you can convert your functions to "arrow functions" to get a more concise syntax.

const arrayStd = [
  ["G14", 18],
  ["G16", 17],
  ["G16", 17],
  ["G13", 17]
];

const arrayToString = array => array.map(a => a.join(":")).join("; ")

var str = arrayToString(arrayStd);
console.log(JSON.stringify(str));

I also changed var to const, which is a good idea for variables you won't modify.

Upvotes: 2

Mohammad Usman
Mohammad Usman

Reputation: 39322

You can use .map() and .join() like this:

let str = arrayStd.map(a => a.join(":")).join("; ");

Demo:

let arrayStd = [["G14", 18], ["G16", 17], ["G16", 17], ["G13", 17]];

let str = arrayStd.map(a => a.join(":")).join("; ");

console.log(str);

Upvotes: 4

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