怎么样在js中实现两个数字相加?
<input type="text" id="a1" value="1"> + <input type="text" id="a2" value="1"> = <input type="text" id="a3" readonly="true"> <br> <input type="button" value="click" onclick="foo()"> <script> function foo(){ a3.value = parseInt(a1.value) + parseInt(a2.value); } </script>