單擊提交按鈕時如何在下拉列表中獲取選定的值

Question

單擊提交按鈕后，如何在下拉列表中獲取選定的值？ 所選值應顯示在控制台中。 我正在獲取選定的值，但在3個值的數組中。

<div class="form-group">
                                     <label class="col-md-4 control-label">City</label>
                                     <div class="col-md-8 inputGroupContainer">
                                            <select name="drop"  onchange="a()">
                                                    <option ></option>
                                                    <option>Bangalore</option>
                                                    <option >HYD</option>
                                                    <option >RJY</option>
                                                  </select>
                                     </div>
                                  </div>
 <input type="button" class="btn btn-primary" onclick="getData()" value="Submit">

這是Js代碼：

var user = {
    name : "",
    fname : "",
    posaddress :"",
    peraddress : "",
    gender : "",
    city :"",

};

var sdvalues = [];
function getData(){
    user.name = document.getElementById("fullName").value;
    user.fname = document.getElementById("fName").value;
    user.posaddress = document.getElementById("addressLine1").value;
    user.peraddress = document.getElementById("addressLine2").value;
    user.state = document.getElementById("state").value;

   var gen = document.getElementsByName("gender");
   for(i=0; i<gen.length; i++) {
       if(gen[i].checked){
         user.gender = gen[i].value;
       }

   }
  console.log(user);
       }

       function a(){
           var ddown = document.getElementsByName("drop");
           for(i=0; i<ddown.length; i++){
            sdvalues.push(ddown[i].options[ddown[i].selectedIndex].value);{
                user.city = sdvalues;

               }

           }

    }

我需要從下拉列表中選擇一個值

Answer 1

  function a(){ var e = document.getElementsByName("drop")[0]; var selected= e.options[e.selectedIndex].value; console.log(selected); } 

  <select name="drop" onchange="a()"> <option ></option> <option>Bangalore</option> <option >HYD</option> <option >RJY</option> </select> 

Answer 2

如果您要修改html，則可以將“ drop”從名稱更改為id，以便將整個選擇作為單個元素獲取，其值將是所選字符串。

 function a(){ var dDown=document.getElementById("drop");//by id gives just one element, the whole thing console.log(dDown.value);//and its value is what you want } 

 <select id="drop" name="drop" onchange="a()"> <option ></option> <option>Bangalore</option> <option >HYD</option> <option >RJY</option> </select>