JSFiddle - React, Tailwind, and code Playground

by Naveen Kumar

HTML

<input type="button" value="Select" onmousedown="selectCup(); return false">
 <input type="text" id="select_text">
     
     <br><br><br><input type="text" id="test" value="Sample Text in this textbox">

JavaScript

function selectCup() {
    
    var search_text = document.getElementById("select_text").value;
    var n = search_text.length;
    var input = document.getElementById("test");
    var input_text = input.value;
    var x = input_text.indexOf(search_text);
    var y = x+n;
    input.focus();
    input.setSelectionRange(x, y); // Highlights "Cup"
};