Si elimino el formulario 1, entonces la etiqueta form2, form3, form4 automáticamente tiene que cambiar a form1, form2, form3 como vice, si elimino el formulario form2, entonces la etiqueta form3, form4 tiene que cambiar a form2, form3.
function delete1(){ (document.getElementById('form1').style.display = 'none') } function delete2(){ (document.getElementById('form2').style.display = 'none') } function delete3(){ (document.getElementById('form3').style.display = 'none') } function delete4(){ (document.getElementById('form4').style.display = 'none') } <div id="form1"> <label class="class1">form 1</label> <button onclick="delete1()">Delete</button> </div> <div id="form2"> <label class="class2">form 2</label> <button onclick="delete2()">Delete</button> </div> <div id="form3"> <label class="class3">form 3</label> <button onclick="delete3()">Delete</button> </div> <div id="form4"> <label class="class4">form 4</label> <button onclick="delete4()">Delete</button> </div>Espero que el siguiente código te ayude
function delete1(){ (document.getElementById('form1').style.display = 'none') resetName() } function delete2(){ (document.getElementById('form2').style.display = 'none') resetName() } function delete3(){ (document.getElementById('form3').style.display = 'none') resetName() } function delete4(){ (document.getElementById('form4').style.display = 'none') resetName() } function resetName() { var div_list = document.querySelectorAll('.form'); var div_array = [...div_list]; // converts NodeList to Array div_array.filter(d=>d.style.display != 'none').forEach((div,i) => { div.querySelector("label").innerText = "form " + (i+1) }); } <div id="form1" class="form"> <label class="class1">form 1</label> <button onclick="delete1()">Delete</button> </div> <div id="form2" class="form"> <label class="class2">form 2</label> <button onclick="delete2()">Delete</button> </div> <div id="form3" class="form"> <label class="class3">form 3</label> <button onclick="delete3()">Delete</button> </div> <div id="form4" class="form"> <label class="class4">form 4</label> <button onclick="delete4()">Delete</button> </div>En su archivo js, recorra todos los formularios, verifique si se muestra! = 'ninguno', luego cambie el HTML interno del texto de su formulario y la identificación de su formulario al índice específico o cadena formateada.