Step 1) Add HTML:
<!-- The text field -->
<input type="text" value="Hello World" id="myInput">
<!-- The button used to copy the text -->
<button onclick="myFunction()">Copy text</button>
Step 2) Add JavaScript:
function myFunction() {
/* Get the text field */
var copyText = document.getElementById("myInput");
/* Select the text field */
copyText.select();
copyText.setSelectionRange(0, 99999); /*For mobile devices*/
/* Copy the text inside the text field */
document.execCommand("copy");
/* Alert the copied text */
alert("Copied the text: " + copyText.value);
}
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