How to Update the Select Box With JavaScript
- 1). Right-click the HTML file that contains your select box. Select "Open With," then double-click your preferred HTML editor in the program list.
- 2). Type the following code in the body of the HTML:
<script type="text/javascript> </script>
Place all of your JavaScript code within these two HTML tags. - 3). Type the following code to update the list of options in the drop-down select box:
var new_item = document.createElement("option");
optn.text = "My New Value";
optn.value = "Value";
selectbox.options.add(new_item);
Replace "selectbox" with the HTML ID for your drop-down select box. The second and third lines of code identify the value and text displayed in the drop-down box. - 4). Save the code in the editor and open the HTML page in a Web browser. Notice the new item updates on the select box.
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