I took the idea presented by Geek Num 88 and extended it to fully meet my need. I didn't know about the ability to overwrite the attribute, which was great! The problem continued to be that I needed to run submitPage() if all is good, and that method's parameters and call could be different per page. That ended up being trickier than just a simple call on success. Here's my final code:
document.observe("dom:loaded", function() {
var allButtons = $$('input[type=button]');
allButtons.each(function (oneButton) {
if (oneButton.value === 'Save') {
var originalSubmit = oneButton.readAttribute('onclick');
var originalMethod = getMethodName(originalSubmit);
var originalParameters = getMethodParameters(originalSubmit);
oneButton.writeAttribute('onclick', null);
Element.observe(oneButton, 'click', function (e) {
if (validateForm(e)) {
return window[originalMethod].apply(this, originalParameters || []);
}
}, false);
}
});
});
function getMethodName(theMethod) {
return theMethod.substring(0, theMethod.indexOf('('))
}
function getMethodParameters(theMethod) {
var parameterCommaDelimited = theMethod.substring(theMethod.indexOf('(') + 1, theMethod.indexOf(')'));
var parameterArray = parameterCommaDelimited.split(",");
var finalParamArray = [];
parameterArray.forEach(function(oneParam) {
finalParamArray.push(oneParam.trim().replace("'","", 'g'));
});
return finalParamArray;
}