function myFunction() { alert("Hello World!"); }
<button>Try it</button>
function myFunction(var1,var2) { 这里是要执行的代码 }
<script> function myFunction(name,job) { alert("Welcome " + name + ", the " + job); } </script>
<button>点击</button>
function myFunction() { var x=5; return x; }