In a web application, calls to an API should be made when you need to retrieve or send data to a server. This can be done in various scenarios, such as fetching data for displaying on a webpage, submitting form data, or performing actions that require server-side processing.
To make a call to an API in JavaScript, you can use the fetch() function or make use of libraries like Axios or jQuery’s AJAX. Here’s an example using the fetch() function:
fetch('https://api.example.com/data') .then(response => response.json()) .then(data => { // Process the retrieved data here console.log(data); }) .catch(error => { // Handle any errors that occur during the API call console.error(error); });
In this example, we are making a GET request to the URL 'https://api.example.com/data'. The response from the API is then converted to JSON format using the response.json() method. Finally, we can access and process the retrieved data in the data variable.
For HTML format, you can include the JavaScript code within a <script> tag in your HTML file. Here’s an example:
<!DOCTYPE html> <html> <head> <title>API Call Example</title> </head> <body> <h1>API Call Example</h1> <script> fetch('https://api.example.com/data') .then(response => response.json()) .then(data => { // Process the retrieved data here console.log(data); }) .catch(error => { // Handle any errors that occur during the API call console.error(error); }); </script> </body> </html>
By including the JavaScript code within the <script> tag, the API call will be made when the HTML page is loaded, and the retrieved data will be logged to the browser’s console.