The select drop-down box is selected by default

This time I will bring you the select drop-down box that is selected by default. What are the precautions that are selected by default in the select drop-down box? The following is a practical case, let’s take a look.

This article mainly introduces the methods related to select drop-down box.

1. Get the value and text value of the drop-down box through id

For example:

<select class="form-control" id="numbers">
      <option value="1">数字1</option>
      <option value="2" selected>数字2</option>
</select>
$("#numbers option:selected").val(); 获取到下拉框被选中的optionde value值：2；
$("#numbers option:selected").text(); 获取到下拉框被选中的optionde 文本内容：数字2；

2. Select a select value by default: add the selected attribute

Enter a number in the input box, call the selectNumber() method when the focus is lost, and select the same number as in the input box

function selectNumber(){
var num = $("#num").val(); //获取input中输入的数字
var numbers = $("#numbers").find("option"); //获取select下拉框的所有值
for (var j = 1; j < numbers.length; j++) {
if ($(numbers[j]).val() == num) {
$(numbers[j]).attr("selected", "selected");
}
} 
}

I believe you have mastered the method after reading the case in this article, more Please pay attention to php Chinese websiteOther related articles for exciting content!

Recommended reading:

How to implement the toggle method in jQuery

How to use the select component in jquery

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