如何在选项标签中显示javascript变量

时间:2016-06-22 20:27:53

标签: javascript html dom

我需要显示一个在选项块的javascript脚本中声明的变量。将有一到两个选择块依赖于此块中选择的选项。

    <select name="expiration_year" id="expiration_year" onchange="populate(this.id,'expiration_month','expiration_day')">

    <script>
    //variable declaration in JavaScript
    var year =  new Date().getFullYear();
    </script>

    //I want to display the variable stored in "year" where it is marked in the 
    //following code
    //this <option value=year> is using the variable correctly, the second 
    //half of the line isnt using the variable (which should have a value 
    //equaling the current year)
    //instead it simply says year
    <select>
    <option value=year>year</option>
    <option value=year+1>year+1</option>

    </select>        

Image of what current code produces when run

任何帮助都将非常感激,我非常新编码网页和使用java脚本。对不起,如果这个问题已被提出并得到解答,我很抱歉。

1 个答案:

答案 0 :(得分:0)

您可以动态添加选项。

e.g。

// This assumes that this is the only select element on the page.
// Also, this would have to run in a script block 
// after the select element is added to the page.
var select = document.querySelector('select');
select.options.add(new Option(year));
select.options.add(new Option(year + 1));

// etc.