get value from textbox in vanilla javascript

JavaScript
document.getElementById("myText").value = "Johnny Bravo";
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Get Text Input Field Value in JavaScript</title>
</head>
<body>
    <input type="text" placeholder="Type something..." id="myInput">
    <button type="button" onclick="getInputValue();">Get Value</button>
    
    <script>
        function getInputValue(){
            // Selecting the input element and get its value 
            var inputVal = document.getElementById("myInput").value;
            
            // Displaying the value
            alert(inputVal);
        }
    </script>
</body>
</html>
Source

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