Question

以下是所有细节

<form action="order.php" method="post" name="myForm" onsubmit="return(validate());">
<input type="text" list="From" name="From" autocomplete="off" placeholder="From Place">
<datalist id="From">
   <option value="Bankura Bus Stand">
   <option value="Bankura Hospital">
   <option value="Katjuridanga">
   <option value="Lokepur">
</datalist>
  <datalist id="To">
  <option value="Bankura Bus Stand">
  <option value="Bankura Hospital">
  <option value="Katjuridanga">
  <option value="Lokepur">
</datalist>

Javascript验证

<script>
    function validate() {
       if (document.myForm.From.value == "") {
       alert("Please select From Place.!");
       return false;
       if (document.myForm.To.value == "") {
       alert("Please select From Place.!");
       return false;
</script>

一切正常，但我只想要选项值，否则显示警告错误：点击提交按钮

<input type="submit" value="Book Now">

我想通过相同的脚本程序...提前致谢

Answer 1

使所有选项值array并使用它测试输入值。

Array.from() method从array-like或iterable创建一个新的Array实例对象。
Array#map() 方法创建一个new array，其结果是调用提供的结果对此array。
indexOf()方法返回可在数组中找到给定元素的第一个索引，如果不存在则返回-1。

＆＃13;

function validate() {
  var fromVal = document.myForm.From.value;
  var toVal = document.myForm.To.value;
  var from = document.getElementById('From');
  var to = document.getElementById('To');
  var optionValuesArrFrom = Array.from(from.options).map(function(elem) {
    return elem.value;
  });
  var optionValuesArrTo = Array.from(to.options).map(function(elem) {
    return elem.value;
  });
  if (fromVal == "") {
    alert("Please select From Place.!");
    return false;
  } else if (optionValuesArrFrom.indexOf(fromVal) === -1) {
    alert("item not in from list.!");
    return false;
  } else if (toVal == "") {
    alert("Please select To Place.!");
    return false;
  } else if (optionValuesArrTo.indexOf(toVal) === -1) {
    alert("item not in to list.!");
    return false;
  }
}

＆＃13;

<form action="order.php" method="post" name="myForm" onsubmit="return(validate());">
  <input type="text" list="From" name="From" autocomplete="off" placeholder="From Place">
  <datalist id="From">
    <option value="Bankura Bus Stand"></option>
    <option value="Bankura Hospital"></option>
    <option value="Katjuridanga"></option>
    <option value="Lokepur"></option>
  </datalist>
  <input type="text" list="To" name="To" autocomplete="off" placeholder="To Place">

  <datalist id="To">
    <option value="Bankura Bus Stand">
      <option value="Bankura Hospital">
        <option value="Katjuridanga">
          <option value="Lokepur">
  </datalist>
  <input type="submit" value="Book Now">
</form>

＆＃13;

需要Datalist选项验证

1 个答案:

Fiddle Demo