Adding Options

Rick Johnson Aug 3, 2005

General

Add or change options on a form select menu. Simple script, includes comments.

Notes

Created by: Rick Johnson
Web Site: http://www.vistaviews.net/
Posted: August 3, 2005

Source Code

Paste this source code into the designated areas.

External file

Paste this code into an external JavaScript file named: addingOptions.js

function buildSelect(x) {
  if (x == "12") { 
    /* set choices 1 and 2 */
    option0 = new Option("  Please Select  ",0)
    option1 = new Option("Value 1",1)
    option2 = new Option("Value 2",2)
    // write them
    document.form1.fieldB.options[0] = option0
    document.form1.fieldB.options[1] = option1
    document.form1.fieldB.options[2] = option2
    return;
    }

  if (x == "34") { 
    /* set choices 3 and 4 */ 
    option0 = new Option("  Please Select  ",0)
    option1 = new Option("Value 3",1)
    option2 = new Option("Value 4",2)
    // write them
    document.form1.fieldB.options[0] = option0
    document.form1.fieldB.options[1] = option1
    document.form1.fieldB.options[2] = option2
    return;
    }

  if (x == "1234") { 
    /* set choices 1,2, 3, and 4 */ 
    option0 = new Option("  Please Select  ",0)
    option1 = new Option("Value 1",1)
    option2 = new Option("Value 2",2)
    option3 = new Option("Value 3",3)
    option4 = new Option("Value 4",4)
    // write them
    document.form1.fieldB.options[0] = option0
    document.form1.fieldB.options[1] = option1
    document.form1.fieldB.options[2] = option2
    document.form1.fieldB.options[3] = option3
    document.form1.fieldB.options[4] = option4
    return;
    }

  if (x == "00") { 
    /* set choices to none */ 
    option0 = new Option("  None  ",0)
    option1 = new Option("",1)
    option2 = new Option("",2)
    option3 = new Option("",3)
    option4 = new Option("",4)
    // write them
    document.form1.fieldB.options[0] = option0
    document.form1.fieldB.options[1] = option1
    document.form1.fieldB.options[2] = option2
    document.form1.fieldB.options[3] = option3
    document.form1.fieldB.options[4] = option4
    return;
    } 
}

Head

Paste this code into the HEAD section of your HTML document.


<script type="text/javascript" src="addingOptions.js"></script>

Body

Paste this code into the BODY section of your HTML document


<form name="form1">
<select name="fieldB">
<option size="15">  Select from below  </option>
</select>
<br>
<input type="radio" name="choice" onclick="buildSelect(12)">Add choices 1 and 2<br>
<input type="radio" name="choice" onclick="buildSelect(34)">Add choices 3 and 4<br>
<input type="radio" name="choice" onclick="buildSelect(1234)"> Add all choices<br>
<input type="radio" name="choice" onclick="buildSelect(00)">Clear all choices
</form>

Leave a Response

(3 comments)

While the general idea is there this code is sloppy because it fails to remove blank entries, but instead only makes them blank. The script should start by clearing all entries (length=0) before writing new ones.

Jeremy Jun 19, 2007

The code is easy to understand, but I would want to add deleting option part to the code. If someone choose 'all choices' and then choose '1&2', the code will still leave '3&4' in it. It could be easily edited by setting those unused options to null.

AsianGrad Feb 28, 2007

My mom is trying to do something similar.She is trying to make it so you chose something from one dropdown menu, it will change the options in another. I sent her the URL to this script, so she could get a little help.TG for this script.

Hayhay Feb 4, 2007

Alphabetical Listing

Tutorials

Ajax Tutorials

Ajax

Buttons

Cookies

CSS

Forms

Games

Generators

Image Effects

Math Related

Miscellaneous

Multimedia

Navigation

Page Details

Password

Snippets

Text Effects

Time & Date

User Details