how to prepend new item to array in typescript

Question

i need to prepend value in typescript objects array

Example if array is

[
   {'title':'this is post title1','content':'this is post content1'},
   {'title':'this is post title2','content':'this is post content2'},
   {'title':'this is post title3','content':'this is post content3'},
   {'title':'this is post title4','content':'this is post content4'},
   {'title':'this is post title5','content':'this is post content5'},
]

i want when i put new item in the first of this array like prepend in jQuery

[
   {'title':'this is new item title','content':'this is new item content'},
   {'title':'this is post title1','content':'this is post content1'},
   {'title':'this is post title2','content':'this is post content2'},
   {'title':'this is post title3','content':'this is post content3'},
   {'title':'this is post title4','content':'this is post content4'},
   {'title':'this is post title5','content':'this is post content5'},
]

thanks in advance

Same way as in JS. typescript tag is for TS-specific questions. — Estus Flask
– Estus Flask, Commented Mar 9, 2018 at 13:40
.unshift() TypeScript is a syntactic sugar of JavaScript. So You should google JavaScript a developer.mozilla.org/pl/docs/Web/JavaScript/Referencje/Obiekty/… — Anton Temchenko
– Anton Temchenko, Commented Mar 9, 2018 at 13:43
Possible duplicate of How can I add new array elements at the beginning of an array in JavaScript? — Mohammad Usman
– Mohammad Usman, Commented Mar 9, 2018 at 13:50
The example you gave is javascript. You should create a class in typescript for it. — Jeroen van Langen
– Jeroen van Langen, Commented Mar 9, 2018 at 14:03

Andrew Lively · Accepted Answer · 2018-03-09 13:40:14Z

9

You can use unshift to prepend items to an array:

const myArray = [ 2, 3, 4 ]

myArray.unshift(1)

console.log(myArray); // [ 1, 2, 3, 4 ]

You can find the docs here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/unshift

answered Mar 9, 2018 at 13:40

Andrew Lively

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CharybdeBE · Accepted Answer · 2018-03-09 13:39:31Z

8

You can use the ... operator

Eg :

 let myArray = [ 1,2,3,4,5 ];
 myArray = [0, ...myArray];

answered Mar 9, 2018 at 13:39

CharybdeBE

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Jeroen van Langen · Accepted Answer · 2018-03-09 13:58:25Z

2

It cannot be done with jquery, because it is functionality belongs to the javascript array object.

You could use the array function unshift() for that.

edited Mar 9, 2018 at 13:58

answered Mar 9, 2018 at 13:39

Jeroen van Langen

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Malcor · Accepted Answer · 2018-03-09 14:00:13Z

2

You can solve it with splice.

arr.splice(index, 0, item);

From another SO question

answered Mar 9, 2018 at 14:00

Malcor

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