php - only submit is check box is checked -

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• <form> if no checkbox selected, alert! .. else .. submit. (javascript) 3 answers

<div id="checkbox">     <input type="checkbox" id="1" name="1"/><br/> <input type="checkbox" id="2" name="2"/><br/> <input type="checkbox" id="3" name="3"/><br/> <input type="submit" value="create"/> </div> 

i have above code , need sort of check form submits if @ least 1 box checked wont submit if 2 boxes checked, checks make sure 1 checked.

many thanks

i suggest use radio buttons group. may follow reference

with radio button, don't need use javascript. if insist use checkbox, using javascript 1 of solution.