Array of string toUpperCase() doesn't work

Question

I have following string array

let example = ["hello", "what"];

I want to convert this array's to this:

 ["Hello", "what"];

To accomplish that I have following code:

example[0][0] = example[0][0].toUpperCase();

When I try to console.log(example), I get

["hello", "what"]

What's wrong here? How can I convert first element's first letter to upper case?

Strings cannot be changed. You have to make a completely new string and replace example[0]. — Pointy
– Pointy, Commented Feb 2, 2020 at 16:33
@Pointy Yes, that's the correct answer, but why we cannot directly modify a string? — Mehmet Ali
– Mehmet Ali, Commented Feb 2, 2020 at 16:41
Do you only want "Hello" to be capitalized, and not also "what", as the question states? — Jake Worth
– Jake Worth, Commented Feb 2, 2020 at 16:48

Refat Alsakka · Accepted Answer · 2020-02-02 16:38:39Z

2

I hope that can help.

let example = ["hello", "what"];

example = example.map(ar => ar[0].toUpperCase() + ar.slice(1));

answered Feb 2, 2020 at 16:38

Refat Alsakka

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Comments

Zabih Ullah · Accepted Answer · 2020-02-02 16:57:43Z

1

Try this one

example = ["hello", "eat"];
var camelCaseArray = [];
for(var x = 0; x < example.length; x++){
    camelCaseArray.push(example[x].charAt(0).toUpperCase()+example[x].slice(1));
}
console.log(camelCaseArray)

answered Feb 2, 2020 at 16:57

Zabih Ullah

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Comments

Sohail Ashraf · Accepted Answer · 2020-02-02 17:22:08Z

0

Try this.

let example = ["hello", "what"];

example[0] = example[0].charAt(0).toUpperCase() +  example[0].substring(1);

console.log(example);

edited Feb 2, 2020 at 17:22

answered Feb 2, 2020 at 16:48

Sohail Ashraf

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1 Comment

BlackWiCKED Over a year ago

Does not provides the required result. The second string should be lowercase.

Sachintha Nayanajith · Accepted Answer · 2020-02-02 17:41:43Z

0

try this one too.

let example = ["hello", "what"];

example[0] = example[0].charAt(0).toUpperCase() + example[0].slice(1);
console.log(example);

edited Feb 2, 2020 at 17:41

answered Feb 2, 2020 at 17:34

Sachintha Nayanajith

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Comments

user4723924 · Accepted Answer · 2020-02-02 16:38:18Z

-1

Why do you have two square brackets? You only need one...

example[0]=example[0].toUpperCase();

answered Feb 2, 2020 at 16:38

user4723924

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1 Comment

BlackWiCKED Over a year ago

That produces: ["HELLO","what"]

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