How to call functions in javascript

Calling a function in JavaScript involves the following steps: Identifying and defining the function. Pass parameters (if required). Use parentheses to call functions. Handle function return value, if present.

Calling a function in JavaScript

Calling a function in JavaScript is a simple and straightforward process that involves Following steps:

1. Identify and define the function

First, you need to identify or define the function you want to call in your code. Functions are typically defined by using the keyword function and the function name, followed by a parameter list within parentheses, and then the function body within curly braces.

For example:

<code class="javascript">function greet(name) {
  console.log("Hello, " + name + "!");
}</code>

2. Pass parameters (optional)

If the function requires parameters, you need to pass them when calling it. Parameter values ​​are passed to the function in order and assigned to the function parameter variables.

For example, to call the greet function above and pass "John" as the argument, you would use the following code:

<code class="javascript">greet("John");</code>

3. Call using parentheses Function

Once you have defined a function and passed the necessary parameters, you can call it using parentheses. Add parentheses after the function name, such as:

<code class="javascript">greet();</code>

4. Handle function return value (optional)

If the function returns a value, you can Function calls assigned to a variable get it. For example, the following code stores the return value of the greet function in the message variable:

<code class="javascript">const message = greet("Mary");</code>

Example:

<code class="javascript">function sum(a, b) {
  return a + b;
}

// 调用 sum 函数并传递参数
const result = sum(5, 10);

// 打印函数的返回值
console.log("The result is:", result);</code>

The above code will output the following results:

<code>The result is: 15</code>

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