JSFiddle - React, Tailwind, and code Playground

HTML

<select name="city" onchange="selectionchanged(this)">
        <option value="1" >One</option>
        <option value="2" >Two</option>
        <option value="3" >Three</option>
        <option value="4" >Four</option>
    </select>
    
    <script type="text/javascript">
    
        switch(selectionchanged(e))
        {
            case 0: (e.value == "1") 
            alert("function_one() called");
        
        case 1: (e.value == "2") 
            alert("function_two() called");
        case 2: (e.value == "3") 
            alert("function_three() called");
        case 3: (e.value == "4") 
            alert("function_four() called");
    }
    </script>