What is the correct way to declare a variable in javascript?

luhan
انضم:
2024-07-02 15:11:56

a. const cityName = Lagos;

b. const cityname = "Lagos";

c. const cityName = "Lagos";

d. const CityName = "Lagos";

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blessedtechie
التحكم
انضم:
2024-07-02 16:50:11

Out of the options you provided, the most correct way to declare a variable in JavaScript for the city name is:

c. const cityName = "Lagos";

Here's why:

const: This keyword is used to declare a constant variable. This means the value assigned to the variable cannot be changed later in the code. This is a good practice for things like city names that are unlikely to change.
cityName: This is a clear and descriptive variable name. It uses camelCase (lowercase for the first word and uppercase for subsequent words) which is the convention for variable names in JavaScript.
"Lagos": This is a string literal enclosed in double quotes, which is the appropriate way to store text data like a city name.

blessedtechie
التحكم
انضم:
2024-07-02 16:52:52

There are actually two main ways to declare variables in modern JavaScript: `let `and `const`. Both are block-scoped, meaning their scope is limited to the block of code they are declared in (like an if statement or a function).

Using `let `allows you to reassign a value to the variable later in your code. This is useful for variables that will change throughout your program.

On the other hand,` const` is used for variables that should hold a constant value and not be reassigned. This helps prevent accidental modification and improves code readability.

Here's an example:

```
let name = "Alice"; // Declares a variable with let and assigns the value "Alice"
name = "Bob"; // Reassigns the value of name to "Bob"
const PI = 3.14159; // Declares a constant with const and assigns the value of pi
// PI = 3; This would cause an error because PI is constan
```

Generally, it's recommended to use const by default and only use let when you specifically need to reassign the variable. This helps prevent bugs and makes your code more predictable.

luhan
انضم:
2024-07-02 16:54:25

@"blessedtechie"#p521 you are spot on.

jenny
انضم: 2025-08-24 15:11:06
2024-07-25 12:35:57
[[29,37],[9]]
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