There is a rare need for this type of functionality but I have found myself in a couple of situations where I needed it. Here is a quick demo of a button click that is simulated from another event handler. In this case, the button click is invoked by checking a checkbox.
<input type="checkbox" onClick="document.getElementById('theSubmitButton').click();">Check the box to simulate a button click
<input type="button" name="theSubmitButton" id="theSubmitButton" value="Button" onClick="alert('The button was clicked.');">
The button was clicked.
The onClick event handler for the checkbox will access the HTML DOM button object and invoke the
click() method. This simulates the button click and invokes the alert.
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