📅 最后修改于: 2023-12-03 15:20:55.025000 🧑 作者: Mango
USD to INVV is a simple web application that allows users to convert USD (United States Dollar) to INVV (Invalid Value). The application was created to demonstrate a simple example of a currency conversion web application while introducing users to programming concepts such as APIs, HTML, CSS, JavaScript, and Markdown.
The USD to INVV web application uses a simple API (Application Programming Interface) to retrieve current USD to INVV exchange rates. The API used is provided by Open Exchange Rates, a real-time currency exchange rate data provider.
fetch('https://openexchangerates.org/api/latest.json?app_id=YOUR_APP_ID')
.then(response => response.json())
.then(data => console.log(data.rates.INVV));
The above code snippet shows how to retrieve the current exchange rate for converting USD to INVV using the Open Exchange Rates API. To use this API in your own application, you'll need to sign up for an API key and replace YOUR_APP_ID with your actual API key.
The USD to INVV web application uses HTML (Hypertext Markup Language) to structure the web page. Here's a sample HTML code for the application:
<!DOCTYPE html>
<html>
<head>
<title>USD to INVV Converter</title>
<link rel="stylesheet" href="style.css">
</head>
<body>
<h1>USD to INVV Converter</h1>
<form>
<label>USD Amount:</label>
<input type="number" id="usd-amount" required>
<button type="submit">Convert</button>
</form>
<div id="result"></div>
<script src="app.js"></script>
</body>
</html>
The code above creates a simple HTML page that consists of a header containing the application's name, a form with a text input for the USD amount, a button to trigger the conversion, and a result div that displays the INVV amount. The link and script tags are used to link the CSS and JavaScript files to the HTML.
The USD to INVV web application uses CSS (Cascading Style Sheets) to style the HTML elements. Here's a sample CSS code for the application:
body {
font-family: Arial, Helvetica, sans-serif;
margin: 0;
padding: 0;
background-color: #F2F2F2;
}
h1 {
text-align: center;
color: #333;
}
form {
margin: 30px auto;
max-width: 400px;
display: flex;
flex-direction: column;
align-items: center;
}
label {
font-size: 18px;
}
input {
padding: 10px;
font-size: 16px;
border: none;
border-bottom: 2px solid #333;
margin-bottom: 20px;
width: 100%;
}
button {
padding: 10px 20px;
font-size: 16px;
border: none;
background-color: #333;
color: #FFF;
cursor: pointer;
}
button:hover {
background-color: #555;
}
#result {
font-size: 24px;
font-weight: bold;
text-align: center;
margin-top: 30px;
}
The code above styles the HTML elements using CSS. The body element sets the font family, margin, padding, and background color of the page. The h1 element centers and changes the color of the application name. The form element sets the margin, maximum width, flex direction, and align items of the form. The label element defines the font size of the label, and the input element defines the padding, font size, border, and margin of the text input. The button element sets the padding, font size, background color, color, and cursor of the conversion button. Finally, the #result element defines the font size, font weight, and margin of the result div.
The USD to INVV web application uses JavaScript to handle the form submission and API request. Here's a sample JavaScript code for the application:
const form = document.querySelector('form');
const usdAmount = document.querySelector('#usd-amount');
const result = document.querySelector('#result');
form.addEventListener('submit', e => {
e.preventDefault();
fetch(`https://openexchangerates.org/api/latest.json?app_id=${YOUR_APP_ID}`)
.then(response => response.json())
.then(data => result.textContent = usdAmount.value * data.rates.INVV);
});
The code above initializes variables for the form, USD amount input, and result div. It adds an event listener to the form that is triggered when the user submits the form. When the user submits the form, the event listener prevents the default form submission and sends an API request to Open Exchange Rates API with the user input USD amount. When the API response is received, the code multiplies the USD amount with the INVV exchange rate and displays the result in the result div.
The USD to INVV web application is a simple example of a currency conversion web application that introduces users to programming concepts such as APIs, HTML, CSS, and JavaScript. You can use this application code as a starting point to create your own currency conversion web application.