Submitting form using <html:submit> and <html:button>

Hi,

I defined a variable in my ActionForm as "submitAction". And I have serveral buttons in my form as below.

<html:submit property="submitAction" value="Save">
This works and I get submitAction="Save".
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<html:button property="submitAction" value="Delete" onclick="javascript:show('myAction.do?submitAction=Delete&param1=someValue')">

function show(url) {
    window.location.href = url
}

This also works since I append submitAction=Delete in the url. If I omit that then I get submitAction="". It seems that when using JavaScript to submit the form, the property of that button doesn't send as a request parameter. Can someone confirm if that is the case?
-------------------------------------------------------------
<html:select property="newProperty">
    <html:options ......>
</html:select>
<html:button property="submitAction" value="Add Property" onclick="javascript:checkProp()">

I want to alert user if the new property already added, and stop then; or call my action if it is new property. 
function checkProps() {
    //check redundancy
    if (redundant) {
        alert(...);
        return;
    } 
    myform.submitAction="Add Property";    **
    myform.submit();
}
I got submitAction="" even with line **. Any thoughts?


Thanks in advance!


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