No puedo realizar dos acciones (es decir, necesito deshabilitar y deseleccionar la opción seleccionada de la selección)
const checkFun = ( value ) => { if( value == '1' || value == '3' ) { document.getElementById("select_two").disabled = true; document.getElementById("select_two").options[0].selected = "selected"; } else { document.getElementById("select_two").disabled= false } } Select One: <select name="testOne" id="select_one" onchange="checkFun( this.value )"><option value="1">1</option><option value="2">2</option><option value="3">3</option></select> Select Two: <select name="testTwo" id="select_two"><option value=""> - please select - </option><option value="test1">test1</option><option value="test2">test2</option><option value="test3">test3</option></select>Gracias
agregue el atributo de valor a - seleccione - etiqueta de opción como value="0"
<select id="select_one"> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> </select> <select id="select_two"> <option value="0"> - please select - </option> <option value="test1">test1</option> <option value="test2">test2</option> <option value="test3">test3</option> </select> <script> const boxTwo = document.getElementById('select_two'); document.getElementById('select_one').addEventListener('change',function(){ boxTwo.value = 0; if (this.value == 2) { boxTwo.disabled = false; }else{ boxTwo.disabled = true; } },{passive:true}); </script>está funcionando como se esperaba!
const checkFun = (value) => { if (value == '1' || value == '3') { document.getElementById("select_two").disabled = true; document.getElementById("select_two").options[0].selected = true; } else { document.getElementById("select_two").disabled = false } } <select name="test1" id="select_two"> <option value=""> - please select -</option> <option value="test1">test1</option> <option value="test2">test2</option> <option value="test3">test3</option> </select> <select name="test" id="select_one" onchange="checkFun( this.value )"> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> </select> function checkFun(value) { const s2 = document.getElementById("select_two"); s2.value = ""; s2.disabled = (value == '1' || value == '3'); } <select name="test" id="select_one" onchange="checkFun( this.value )"> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> </select> <select name="test1" id="select_two" disabled> <option value=""> - please select -</option> <option value="test1">test1</option> <option value="test2">test2</option> <option value="test3">test3</option> </select>