JS gets the value in the first element in the select drop-down box

This time I will bring you JS to get the value in the first element in the select drop-down box, and JS to get the value in the first element in the select drop-down box. What are the things to note? are as follows. This is a practical case, let’s take a look at it.

The example of this article describes the method of JavaScript to obtain the first value in the select drop-down box. Share it with everyone for your reference, the details are as follows:

1. Description

Get the first value in the select drop-down box

2. Implement the source code

nbsp;html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">


<meta>
<title>JavaScript获取select下拉框中的第一个值</title>
<script>
   /**
   * JavaScript获取select下拉框中的第一个值
   */
   function getFirstValOfSelect()
   {
     //获取select中的ID
     var selectId = document.getElementById("select_option");
     //获取select下拉框中第一个值
     var selectValue = selectId.options[0].value;
     //获取select下拉框中第一个文本值
     var selectText = selectId.options[0].text;
     //打印select下拉框中第一个值和文本值
     alert("值：" + selectValue + "\n" + "文本值：" + selectText);
   }
</script>


  <p>
    <select>
      <option>桃树</option>
      <option>梨树</option>
      <option>樟树</option>
      <option>枫树</option>
      <option>松树</option>
      <option>梧桐树</option>
      <option>槐树</option>
    </select>
  </p>
  <input>

3. Implement the result

(1) Select the first item

(2) Select the second item

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

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