Javascript how to run same function onLoad and onChange
I have a form that has many favorites menus, most of them are Yes / No, and depending on the option I choose, I show / hide some additional options. One of the selected menus is the following:
<td><%= f.select :CBIAvailable, ['Yes' , 'No'],{}, {:id=>"cbi_available_id", :class=>"cbi_available_class", :onChange=>"showHideOptions('cbi_available_id','cbi_options_id')", :onLoad=>"showHideOptions('cbi_available_id','cbi_options_id')"} %></td>
When I switch from "Yes" to "No" or vice versa, the showHideOptions javascript functions are called as expected, but I cannot call this function on form reload.
Can anyone tell me what I am doing wrong?
thank
UPDATE
<script language="javascript" type="text/javascript">
function showHideOptions(selectorId,optionsId) {
if (document.getElementById) {
var selector = document.getElementById(selectorId);
var options = document.getElementById(optionsId);
if (selector.value == 'Yes') {
options.style.display = 'block';
return false;
} else {
options.style.display = 'none';
return false;
}
}
window.onLoad = showHideOptions('cbi_available_id','cbi_options_id');
source to share
function yourFunction(){
//get that select element and evaluate value
//do you change stuff here
}
window.onload = yourFunction; //this gets fired on load
//"select" is your element,
//fetched by methods like document.getElementById();
select.onchange = yourFunction; //this gets fired on change
//you can also use attachEvent (IE) or addEventListener (Others)
here's a working demo :
<select id="testSelect">
<option value="yes">YES</option>
<option value="no">NO</option>
</select>
function getOption() {
alert('foo');
}
var select = document.getElementById('testSelect');
select.onchange = getOption;
window.onload = getOption;
source to share
This can happen when you receive a postback from a remote server and your response has no <script type="javascript">... yourfunction()...</script>
.
Every time you get a new response you have to send the script and exacute it or add it to your html event handler.
Another solution is to use jQuery and use . live () event. This event adds dynamic behavior to your html. I highly recommend using jQuery live because it is one of the most commonly used libraries in production.
Edit
<script type="text/javascript" src="path_to_jquery.js"></script>
<script type="text/javascript">
function showHideOptions(id1,id2){
//Your code
}
$(document).ready(function() {
//This function waits for DOM load
//execute your function for first time
showHideOptions('cbi_available_id','cbi_options_id');
//This selector you have to modify or show us generated html to
// choose the best selector for this purpose
$('.cbi_available_class').live('change',function(){
//This will fire change event of html class="cbi_available_class"
showHideOptions('cbi_available_id','cbi_options_id');
});
});
</script>
source to share